Water, Hydrogen, and Oxygen, and where we get our energy

 

The above equation is a simple way of showing what happens during photosynthesis. There are more detailed ways to show it. Photosynthesis is a complicated process, or processes. But, at its heart, it may be summarized simply.

As you know, there's a lot of water on the earth. As you also know, water consists of two elements, Hydrogen and Oxygen. As you may not know, the energy you need is intimately connected to water. I'm using energy to type this, and you are using energy to move your eyes as you read it. What's that got to do with water?

Our food comes from photosynthesis. Green plants absorb light, and produce various molecules that we use as food, such as starches, sugars, several vitamins, and proteins.

 Light energy is used to split water, and the Hydrogen split off is then available for the manufacture of Carbon-containing molecules, like glucose, food molecules, which can be stored, broken down to release energy, or moved to parts of the organism where they are needed. Some of the need is to release energy. Most foods you buy at a grocery store, or a restaurant, come with a calorie number. That number indicates the amount of energy you would expect to get if you ate and digested that food. The energy comes from energy-storing molecules, like glucose. The Carbon-containing molecules, which have Hydrogen added to the Carbon, may also be used to produce important molecules like enzymes, vitamins, hormones and proteins. (Oxygen, Nitrogen, Sulfur and other elements may be added to a Carbon-based structure.)

Organic molecules, like glucose, will burn. Burning uses Oxygen to carry on combustion. There is a process, used by nearly all organisms, called cellular respiration. That process also uses Oxygen to create water, and, in the process, releases energy for use in our cells. So, putting it very simply, photosynthesis uses light energy to break water, and cellular respiration puts water back together, and releases energy.

I'm bald-headed. So lots of light hits my head. My cells, like yours, have lots of water. So why doesn't that light, on my scalp cells, split water and make glucose? The answer is that various helping molecules, molecular tools, as it were, are necessary for photosynthesis to occur. These include chlorophyll and several enzymes, which I don't have in my scalp cells.

Isn't God great? Thanks for reading.

The moon can be an absentee ruler: Problems with reading Genesis 1 and 2 as history.

Some Christians believe that Genesis 1 was meant to be read as history, and sets forth events in sequence. (See my previous post for further discussion of interpreting Genesis 1.) 

There are some problems with reading Genesis 1 as history, setting forth events in sequence. Here are some of them:

1) Light appears on the first day, but the sun and moon (which are not named, probably as a warning against worshiping them) are not mentioned until the fourth day.

2) The sun is described as ruling the day, and the moon as ruling the night. Surely the ancient Hebrews (and God!) knew full well that the moon appears during the day on most days, for periods up to almost the entire length of that day, and is not always present during the night. How can the moon rule the night on nights when it doesn't appear?

The above photo, taken in daylight, shows that the moon was clearly visible, and the sun was clearly shining. That means that, on the other side of the earth, neither the moon nor the sun was visible in the sky, at that time. Photo from Laura Suarez (distributed via imaggeo.egu.eu).

3) Genesis 1 describes a firmament (or expanse) as being created on the second day. The problem with that is that there is no firmament. Ancient peoples believed that there was one, and supposed that various celestial objects, and clouds, were held up by this structure. There is no firmament. The moon, the sun, the stars, galaxies, planets, comets and asteroids are not held up by any sort of glass sphere, or invisible framework (unless you count gravity as such). They are at distances that vary by orders of magnitude -- the moon is relatively close to us, the Magellanic Clouds much further away, so that there is no way that both of these could be held up by one structure surrounding the earth. The earth is not the center of the solar system.

How do I explain these problems? Is the Bible wrong?

I would argue that the Bible is not wrong. It was not meant to be a textbook of astronomy, or geology, or biology. It was meant to tell us about God, the single wonderful, wise creator, and His sovereignty over the creation. God used the language and ideas of the culture of the time. People of that day believed that there was a firmament, so God allowed the description of the creation to include this. Today, we say "sunset" and "sunrise," even though the sun doesn't really rise, or set -- the earth's rotation makes it seem that it rises and sets. If, for example, a news reporter or a novelist says that an event happened at sunrise, we don't accuse her of ignorance or deception.* These ideas are part of our culture, and communicate within that culture, whereas saying "the earth rotated so that the sun appeared on the horizon in Central Africa," is unnecessarily cumbersome and confusing. The idea of a firmament, in Bible times, communicated with others.

Added Dec 13, 2021: For more on the firmament and the Hebrews, see here.

Thank you for reading!

*There are other examples of this sort of thing, such as acting as if or communicating that gravity is an attractive force, because it's ingrained in our culture. If I understand Einstein, gravity is because of space being warped, so that two objects travel toward each other in space-time, and it isn't really an attractive force. The more up-to-date Einsteinian explanation of gravity was used frequently in Star Trek. ("warp speed") But we write and talk about falling downstairs, for example.

Another example of how culture makes communication unscientific is the use of heart for the seat of the emotions.

It is likely that some current ideas about how things work, from the submicroscopic to the galactic, will seem foolish to people in the future centuries. (If there are to be future centuries.)

We aren't capable of understanding how God created light - God spoke. In what language?

We aren't capable of understanding how God created, except very superficially. If, for example, we believe that light came about instantaneously because God spoke, what words and language did He use? Did He speak aloud? Was "God" God the Father, God the Son, God the Holy Spirit, or all of them? Was anyone listening? Was light created from something else, or did it just appear? Did it appear throughout the entire universe at the same time? Why does Genesis 1 seem to indicate that light was created on the first day, but the sun and moon were created on the fourth? The moon is a reflecter, not an independent source of light -- did Genesis 1 take that into account? We don't know the answer to these questions, and many others, and aren't going to. If we understood these things fully, we would, in effect, be gods, and we aren't. 

This paragraph is modified excerpt from a longer post on this blog, published in 2013.

Let there be light! I'm thankful for the electromagnetic spectrum

Genesis 1:1 In the beginning, God created the heavens and the earth. 2 The earth was formless and empty. Darkness was on the surface of the deep and God’s Spirit was hovering over the surface of the waters. 3 God said, “Let there be light,” and there was light. 

There is controversy over whether Genesis 1 is to be taken as a sequential account of the creation, or should be interpreted in some other way, and over when and how long creation took place. Let’s put those matters aside. They don’t really matter for the topics of this post. The first reported created act (although the creation of the earth seems to have come first) is bringing light about. That’s important.

Light is important. The main source of usable energy on earth is light. Energy from light drives the water cycle. Light is absorbed by green plants, and almost all of the food we eat exists because of that. Light makes it possible for us to perceive where we are, where we are going, and who and what is around us. Light makes it possible for us to work, and to play. Without light, reading would be difficult or impossible. Except for those unfortunates of us who are blind, we live in a world perceived and navigated because light is present.

The Bible doesn’t say “let there be an electromagnetic spectrum.” Such a term wouldn’t have made sense to the ancient Israelis, and doesn’t make sense to a lot of us today. See here for more about that spectrum. But I will say that visible light is a rather small part of a range of energy forms, ranging from gamma rays, X-rays and ultra-violet to infrared, microwaves and radio waves. The people living when Genesis was written, and when it became a part of their culture, had no way of detecting these other forms, or appreciating their importance. However, whenever and however light came to be, this whole family of energy must have accompanied it. I don’t know about you, but I use WiFi every day. I’m not sure whether my phone uses 5G or not, but, whether it does, or not, it’s using part of the electromagnetic spectrum to help me communicate.

I had a chest X-ray a few weeks ago. That part of the electromagnet spectrum allows us, as it were, to “see” parts of our bodies that we can't see with ordinary light.

We open our blinds frequently. This is partly so we can see our surroundings. It is also to help heat our home without adding to the utility bill. Light is reflected -- that’s how we see, as light is reflected off of whatever we are looking at, and comes back, going through our pupils and striking our retinas. But it is also absorbed, for example by green plants that carry on photosynthesis. Some of the absorption is manifest in that light energy is converted to heat energy, which, when radiated, is another part of the electromagnetic spectrum. Without heat derived from the sun’s light, the earth would be uninhabitably cold.

Some other Biblical thoughts about the electromagnetic spectrum. Here’s a quotation from 1 Timothy: “6:16 He alone has immortality, dwelling in unapproachable light, whom no man has seen, nor can see: to whom be honor and eternal power. Amen.” Unapproachable light? Yes, there is that, physically. We can’t be exposed to parts of the electromagnetic spectrum, in any great amount, or for any great length of time, without suffering damage, or even death. Is the scripture talking about the electromagnetic spectrum, as physicists measure it, or is this symbolic of God’s great holiness and power? Or is it both? I don’t know.

John 8:12 Again, therefore, Jesus spoke to them, saying, “I am the light of the world. [Perhaps referring to Isaiah 60:1] He who follows me will not walk in the darkness, but will have the light of life.” Christ, Himself, illuminates, warms, communicates. He is truly the light of the world. (See John 1:1-9.)

Finally, Revelation 22:4 They will see his face, and his name will be on their foreheads. 5 There will be no night, and they need no lamp light or sun light; for the Lord God will illuminate them. They will reign forever and ever. I don’t pretend to understand this, but its part of the Bible.

Thanks for reading. Image modified from Pixabay. Scripture in this color, from the World English Bible.

30 days of science-oriented Thanksgiving, 2019

Thanks to God for:

1) Light: I'm thankful for light. It's significance is emphasized, as it was the first thing mentioned as created, in the Genesis story. We depend on it so much, and take it for granted -- at least I do.

2) I'm thankful not only for light, but that light is part of the electromagnetic spectrum, meaning that light appears in a range of colors, visible in rainbows and in other ways, and also in mixtures of these colors, such as brown, which doesn't appear in the rainbow. They say that some animals have no color vision. TVs used to be black-and-white only. I'm glad that we can see colors.

3) I’m thankful that light can be reflected. Without reflection, I couldn’t see myself in the bathroom mirror. I couldn’t back my car up safely. I couldn’t see colorful trees reflected in bodies of water. Without reflection, I couldn’t see the moon, which reflects the sun’s light. Telescopes and microscopes use reflection to help us see wonders that we couldn’t’ see without reflection.

4) I’m thankful for a special use of reflected light – reading print. The white part of a printed page (or sign, or food label, or our credit card, or whatever) reflects more light than the dark part – the words. I know that much reading today is not of this sort. I’m reading this as I type because the computer screen emits light, except where the letters are. But we still depend a lot on reading print.

5) I’m thankful for refraction. Refraction means that light is bent as it goes from one medium, like air, into another, like glass or water. Without refraction, I couldn’t see. My eye lenses refract light so that it can be focused on my retina. My glasses refract light, assisting my eye lenses, so that I can see close up. Different colors of light are refracted differently, thus making rainbows possible.

6) I’m thankful for water, the only common substance that can exists in solid, liquid and gaseous form under ordinary conditions. It’s also the only common substance that has a solid that floats on its liquid. Without these properties, the oceans would be solid ice, and we wouldn’t ever get rained on.

7) I’m thankful that water is able to dissolve many other substances. The ancient alchemists were said to be searching for some wondrous things, including the “philosopher’s stone,” that would turn things into gold, and the “universal solvent,” that would dissolve anything. As someone said a long time ago, water is the nearly universal solvent. It can combine with other substances, especially acids, to dissolve even more things. Some geological features are the result of mildly acid water dissolving rocks. Consider, in us: our blood, a solution of many substances in water, carries Oxygen, Carbon Dioxide, hormones, enzymes, antibodies, red and white blood cells, food particles, Nitrogen waste, food waste, and other items, in our blood stream and body fluids, which are all mostly water.

8) I’m thankful that light is a form of energy. Much of the sun’s energy, that keeps the earth warm enough to be livable, has come to earth in the form of light. Light energy can be absorbed, and does various things, many of them important, after such absorption. One such thing is illustrated by the brick wall on the west side of our house. After a sunny afternoon, the bricks have absorbed energy, and feel warm. Light energy, turned to heat, melts snow and ice.

9) I’m thankful for Carbon. Carbon atoms can connect with as many as four other atoms. This makes complicated molecules, like protein, DNA, steroids, cellulose, and many more, possible. If, for example, Carbon could connect with only two other atoms, nothing more complicated than a long chain would be possible. We are called Carbon-based life forms for a good reason. Carbon is an abundant element, and its atoms are light, so some Carbon compounds can enter the air, and, for example, make molecules that we can smell. Coffee, anyone?

10) I’m thankful for what is arguably the most important process on earth – photosynthesis. Light energy is captured by green plants and used to turn Carbon Dioxide and water into food molecules. Food is something we eat that gives us energy (which is measured in calories). Most likely, all the food you have consumed in the past year came from photosynthesis in some green plant. Thank God!

11) I’m thankful for carbohydrates. They are made of Carbon, Hydrogen and Oxygen, and their names usually end in “ose,” as in glucose, fructose, cellulose, and more. Starches are complex carbohydrates. Some of us eat too much carbohydrate, and expand, as a consequence. But we need energy to live, and carbohydrates are a good source of food energy. Cellulose is taken in in the form of fiber, and we should eat fiber, too. Some carbohydrates such as sucrose, common table sugar, taste sweet. I like it, more than I should.

12) I’m thankful for my sense organs. Our tongue and nose can detect certain molecules, apparently because of their 3-dimensional shape. Sugar molecules have a distinctive shape. Sugar molecules fit into sweet-detecting sense structures in the tongue which detect that shape, and these structures send a message to the brain: “that was sweet!” Scientists have figured out how to make sugar substitutes, which have a shape that activates the same sensors, and cause the same message to go to the brain. Sugar substitutes are usually indigestible, or don’t turn into as many calories as sugar, hence you may gain less weight from eating or drinking them than from the equivalent food/drink with sugar in it.

The senses of taste detects various chemicals that touch the tongue. The sense of smell detects molecules that come to the nose through the air. I’m thankful for the smell of coffee, even though I don’t drink it, and for lots of other smell-producing materials. When I was in college, my nose was cauterized to stop frequent nosebleeds. As a result, I don’t have much sense of smell. Be thankful for yours!

13) I’m thankful for deoxyribose, a 5-Carbon sugar that is an essential part of DNA – in fact, DNA is named for it: Deoxyribose Nucleic Acid. As surely you know, your heredity is carried from generation to generation by DNA. It’s also carried from cell to cell in your body. The trillions of cells in your body all came from a single fertilized egg. Most of your cells have the same DNA, with some exceptions. Occasionally you may see someone with two different iris colors, or with strange patches of skin or hair. But these are rare. Your left side mostly mirrors your right. Be thankful for your heredity, and that it’s all the same throughout your body, except for occasional mutations.

In addition to deoxyribose, DNA contains Nitrogen bases and Phosphate. I’m thankful for them, too.

14) I’m thankful for cellulose. Cellulose is a complex carbohydrate, made of hundreds, or more, of glucose molecules strung together. Plants use it as structural material in their cell walls. Since it is structural, it has numerous uses. We get fiber in our diet mostly from plant cell walls in our food. Cotton and linen fibers contain cellulose, so most of us are clothed with this, some of the time. Paper, including cardboard, includes cellulose. Cellulose is the most common constituent of wood, which is used in structures and implements of many kinds, as well as being a fuel.

Without cellulose, there would be no trees, with all the joy, majesty, and utility that they bring. No forests, no leaves falling.

15) I’m thankful for Silicon, an element. It’s the second most abundant element in the earth’s crust, behind Oxygen. In the earth’s crust – the rocks, dirt, etc., that we can access fairly easily with a shovel or a drill – Silicon is almost always in combination with some other elements, like Oxygen or Aluminum. Quartz is mostly Silicon Dioxide. Quartz, mica, feldspar, and other materials make up granite, one of the most common types of rock on earth. Mica and feldspar also contain Silicon. Minerals containing Silicon make up about 90% of the earth’s crust.

16) As yesterday, I’m again thankful for Silicon. Here’s the Wikipedia: “The most widely used silicon device is the MOSFET (metal-oxide-silicon field-effect transistor), which has been manufactured in larger numbers than any other device in history.” In other words, the computer I’m typing this on, and all the devices that could read this, use Silicon-based transistors, in order to do their jobs.

17) I’m thankful for sand. Many sands are mostly Silicon Dioxide. SiO2 sand is the main constituent of glass. Can you imagine life without glass? Touchscreens on smartphones and similar devices contain glass. So do many glasses that people wear. Then there are windows, and drinking glasses, and lots of other stuff. (Some sands, for example from corals, are mostly Calcium Carbonate, but most sands are Silicon Dioxide.) The Wikipedia lists a couple of dozen or so uses for sand.

18) You are breathing it right now, even though you can’t smell it or see it. What is it? Nitrogen, which I’m very thankful for. Nitrogen gas makes up about 80% of the earth’s atmosphere. Oxygen is the second most common gas in the atmosphere. Without that Nitrogen, an increase in Oxygen would mean that fires would spread more rapidly and be more devastating and dangerous.

19) I’m thankful for Nitrogen. DNA, the heredity molecule, has a Nitrogen-containing base in each unit, which means that we probably have trillions of Nitrogen bases in our bodies. The Nitrogen bases, ACGT, make up the genetic code. Nitrogen is also part of every amino acid. Amino acids make up protein, and, of course, we need protein for structure, for making up enzymes, and for other things. Life, as we know it, would be impossible without DNA, its close relative, RNA, ATP, and amino acids. Each of these contains Nitrogen.

20) I’m thankful for Nitrogen-fixing bacteria. We need Nitrogen, which is part of many of the most important molecules in living things. But, even though most of what we breathe is Nitrogen gas, we can’t use that to make amino acids or RNA. We have to get Nitrogen in what we eat. Some bacteria in the soil, often in special structures on the roots of members of the pea family, such as peas, beans, peanuts, alfalfa, clover, and many more, can take Nitrogen from the air in the soil. The plants that they are growing with can access this Nitrogen. Members of the pea family are good sources of Nitrogen, in the form of protein. We can get Nitrogen from other kinds of food, especially food high in protein, but, in most cases, such Nitrogen was first captured by bacteria in the nodules on the roots of plants.

21) I’m thankful for Hydrogen. There are more atoms of Hydrogen than of any other element in the universe. Hydrogen is part of water, which is enough to make it very important, but there’s more. Hydrogen is part of almost all of the molecules of living things, such as carbohydrates, steroids, proteins, lipids, DNA, RNA, ATP and more. It also is part of Hydrocarbons, which we use to make plastics, and burn as fuel in our automobiles. It’s easy to ignore Hydrogen. It doesn’t seem to be the central part of any of these important types of molecule. But it’s there, in all of them. Life would not be possible without it.

22) I’m thankful, again, for Hydrogen. Almost all of the energy we use depends on it. Why? Because there are processes in the sun that take Hydrogen, and fuse it together into Helium, releasing energy in the process. (Hydrogen bombs, if ever used, would engage in similar processes.) Energy released by this nuclear fusion escapes into space, some of it in the form of light, and a small part of it hits the earth, warming it, and providing energy for the food manufacturing processes of photosynthesis.

23) I’m thankful for Oxygen. Oxygen reacts easily. We can see the results in flames, and in rust (which is oxidized iron). Because this is true, living things use it to access energy from the food they make, in photosynthesis, or the food they eat. They oxidize this food, which results in the production of Carbon Dioxide and water, and the release of energy. This oxidation is slower, and much less destructive, than ordinary burning. (Most foods can be burned, giving off energy in a different way.) When we exercise, we need Oxygen, so that we can release energy stored in our bodies. That’s why we may gasp and pant after running, for example – we need Oxygen to replenish our accessible energy.

There are some organisms (you won’t find them in zoos) that get their food, and access the energy from it, in different ways.

24) I’m thankful for Oxygen. Besides the fact that we need to breathe it, Oxygen is part of the essentially all of chemicals that living things are made of. Most living things, including us, are mostly water. Water is a combination of Hydrogen and Oxygen. Besides that, DNA, RNA, ATP, starch, sugar, fats, hormones, vitamins, proteins, and more, all have Oxygen as part of their structures.

25) I’m thankful for metabolism. The rest of this post was extracted from the Wikipedia: “Metabolism … is the set of life-sustaining chemical reactions in organisms. The three main purposes of metabolism are: the conversion of food to energy to run cellular processes; the conversion of food/fuel to building blocks for proteins, lipids, nucleic acids, and some carbohydrates; and the elimination of nitrogenous wastes. These enzyme-catalyzed reactions allow organisms to grow and reproduce, maintain their structures, and respond to their environments. (The word metabolism can also refer to the sum of all chemical reactions that occur in living organisms, including digestion and the transport of substances into and between different cells, in which case the above described set of reactions within the cells is called intermediary metabolism or intermediate metabolism).”

26) I’m thankful for enzymes. Enzymes are proteins that speed up chemical reactions, such as the ones in metabolism (see yesterday’s post). In effect, they make these chemical reactions possible. Without enzymes, they wouldn’t take place at all, or they would be so slow that they wouldn’t do us any good. Enzymes help convert food to useful energy, help convert food molecules to the more complex molecules necessary for life, such as proteins, hormones, DNA and RNA. They help eliminate nitrogenous wastes. They are necessary in the formation of new cells, as when an embryo grows, or an older person replaces dead cells, such as skin cells.

27) I’m thankful for the parts of my body that produce digestive enzymes. The salivary glands produce enzymes that digest starch, breaking it down to sugar. (Chew on a cracker for a few minutes. It will probably begin to taste sweet.) There are enzymes in the stomach that help break down food molecules. These enzymes require an acid environment, in order to work. The pancreas and the liver produce enzymes that help digest food molecules. If food wasn’t digested, it wouldn’t do us any good. We would get just as much good from eating sand as from eating turkey.

28) I’m thankful for Sulfur. It’s one of the more prevalent elements in my body, after Carbon, Hydrogen, Oxygen, Nitrogen, Calcium, and maybe Potassium. Amino acids make up proteins. Proteins can be enzymes, or part of our structure (hair is mostly protein) or perform other functions, such as fighting infection. Two of the amino acids that make up proteins, cysteine and methionine, contain Sulfur. Cysteines bonded together help to give hair, and other body parts, their structure. If hair is burnt, there’s a bad smell, which is mostly due to Sulfur.

Sulfur is a necessary part of sulfuric acid, which is used in making fertilizer, and used in some kinds of batteries. Sulfur is used as a fungicide and pesticide. Some of the most important antibiotics contain Sulfur. Sulfur is necessary for life on this planet.

29) I’m thankful for Sodium. Sodium is part of common table salt, Sodium Chloride. We need Sodium in order to live. However, too much Sodium can lead to high blood pressure, and, if it’s really too much, even to death. Salt is used as a preservative. Sodium is used to manufacture chlorophyll, which is used in photosynthesis, the basic food-making process that we all depend on. Sodium is necessary for the functioning of the nervous system. As you read this, Sodium is migrating across the membranes of your nerve cells, making perception of what you are reading, and thought about it, possible. Yellow colors in fireworks are due to Sodium.

30) I’m thankful for Phosphorus. Phosphorus is an essential part of DNA and RNA, the molecules that carry our genetic code, and help to express it. It’s also part of ATP (Adenosine Triphosphate) which is used in the processes that release energy from food. Our cell membranes contain Phosphorus. It’s no wonder that almost all fertilizers contain Phosphorus.

Many matches contain Phosphorus.

I could have been thankful for Potassium, Calcium, Chlorine, Iron, and other elements of the periodic table, but will stop here. Thanks for reading.

Is the sun important to us? Absolutely

Why is the sun important to us?
 
For starters, the gravitational attraction of the sun holds the earth in a stable orbit, which is necessary for our very existence as living beings on this planet.

The sun is a giant source of energy. Einstein pointed out the relationship between energy and mass, in his famous e = m c-squared equation. Every second, thousands of tons of mass are turned into energy, by the sun. The process involves four Hydrogen nuclei fusing into a Helium nucleus, which has a little less mass than the Hydrogen nuclei. This fusion wouldn’t be possible without the extreme temperature in the core of the sun – millions of degrees. Temperature is a measurement of the velocity of molecules. At absolute zero, all motion ceases. In the core of the sun, the velocity of particles is so high that they can overcome natural forces of mutual repulsion, hence slamming together and fusing nuclei.

In case you didn’t know, the c in Einstein’s equation is the velocity of light, a large number, and it’s squared. That means that a little bit of mass can be converted to a lot of energy.

What happens to the sun’s radiated energy? Most of it goes off into space, perhaps eventually hitting something. The sun is about 93,000,000 miles away from us. Think of a giant sphere, with a diameter that large. The sun’s radiated energy goes off evenly in all directions. The earth occupies only a very small fraction of the surface of that imaginary sphere. But that very small fraction gets hit by a tiny bit of the sun’s emitted energy, and that is very important to us.

Energy from the sun keeps the earth at a temperature compatible with human, and other, life. It is possible that there is life elsewhere in the solar system, but not likely. Either conditions would be too hot for life, or too cold, in most planets and planetary moons, such as the moons of Saturn.
 
Energy from the sun, in the form of light, makes it possible for us to perceive the world around us, using vision. Most insects, most vertebrates, and some other animals use vision, which would be impossible without light from the sun. (Some animals can see types of light that we can’t, but that statement still applies.) We can perceive the world around us in other ways, to be sure, but vision is arguably more important than the other senses we have.

Energy from the sun makes the seasons possible, and also makes various critically important earthly phenomena, such as the water cycle, possible. Energy from the sun makes erosion and weathering of rocks possible.

Energy from the sun, in the form of light, makes photosynthesis possible. Essentially all of the food energy we take in came directly or indirectly from photosynthesis. In photosynthesis, light is captured by green plants, who use it to produce sugars and various other organic substances, that we need to build ourselves, and to release energy to keep us going.

Is the sun important to us? Absolutely. Yes, that’s the right word – absolutely.

Perhaps St. Paul was speaking of the critical importance of light, when, under the inspiration of the Holy Spirit, he wrote “1 Timothy 6:15b who is the blessed and only Ruler, the King of kings, and Lord of lords; 16 who alone has immortality, dwelling in unapproachable light; whom no man has seen, nor can see: to whom be honor and eternal power. Amen. (World English Bible, public domain.)

The first day of creation: things we are never going to understand

Genesis 1:2 The earth was formless and empty. Darkness was on the surface of the deep and God’s Spirit was hovering over the surface of the waters. 3 God said, “Let there be light,” and there was light. 4 God saw the light, and saw that it was good. God divided the light from the darkness. 5 God called the light “day”, and the darkness he called “night”. There was evening and there was morning, the first day. (World English Bible, public domain)

There are plenty of possible questions about this passage, such as about how literally to take it, but I’d rather not explore the questions of what “day” means, and other such matters, important as they might be. I have some other questions in mind, questions that we will never understand in this life, and maybe not in the next one. We can, and may, have opinions about them, but the opinions are not strongly backed by the Scripture, or are not covered at all in the Bible, and Genesis 1 is interpreted in different ways by different people. For more on scriptural interpretation, see this post.

Questions:
If God spoke light into existence, what language did He use?
Does God, in this passage, mean God the Father, God the Son, God the Holy Spirit, or some combination of them?
Who did God speak to?
If He/They spoke to some other entity, who was it, and why was this said?
Did angels, or some other entity, actually create the light, at God’s command?
Was the creation of light preceded (whatever preceded  means to an eternal God!) by planning?
Was the entire electromagnetic spectrum, of which light is only a small part, created at once?
Did the creation of light cost God effort or resources of some sort?
Does this passage actually refer to the creation of the sun, or was that created later?
Was there light elsewhere in the universe, but not on earth, or, on the other hand, was the light created for the earth, or perhaps for the solar system, spread throughout the universe somehow, after this initial creation?
Was light created from something else?

Interesting questions. (There are more questions about origins in this post -- toward the end.) I have no answers. Thanks for reading.

"I am" in the Gospel of John -- important occurrences.

There are about 70 occurrences of the word pair "I am" in John, most rather trivial. Those below are not trivial.

This “I am” is not in John, but is the source of one that is in that Gospel:
Exodus 3:14 God said to Moses, “I AM WHO I AM,” and he said, “You shall tell the children of Israel this: ‘I AM has sent me to you.’”

John 8:58 Jesus said to them, “Most certainly, I tell you, before Abraham came into existence, I AM.” Jesus was referring to the experience of Moses indicated above, and his critical hearers understood that He was doing so.

In John 4, Jesus, in effect, told the Samaritan woman that I am living water. 10 Jesus answered her, “If you knew the gift of God, and who it is who says to you, ‘Give me a drink,’ you would have asked him, and he would have given you living water.” 13 Jesus answered her, “Everyone who drinks of this water will thirst again, 14 but whoever drinks of the water that I will give him will never thirst again; but the water that I will give him will become in him a well of water springing up to eternal life.”

6:35 Jesus said to them, “I am the bread of life. He who comes to me will not be hungry, and he who believes in me will never be thirsty. 47 Most certainly, I tell you, he who believes in me has eternal life. 48 I am the bread of life.

8:12 Again, therefore, Jesus spoke to them, saying, “I am the light of the world. He who follows me will not walk in the darkness, but will have the light of life.”

10:11 I am the good shepherd. The good shepherd lays down his life for the sheep.

11:25 Jesus said to her, “I am the resurrection and the life. He who believes in me will still live, even if he dies. 26 Whoever lives and believes in me will never die. Do you believe this?” [To Martha]

14:6 Jesus said to him, “I am the way, the truth, and the life. No one comes to the Father, except through me. [To Peter. Perhaps other disciples were present.]

15:1 “I am the true vine, and my Father is the farmer. 2 Every branch in me that doesn’t bear fruit, he takes away. Every branch that bears fruit, he prunes, that it may bear more fruit.

18:37 Pilate therefore said to him, “Are you a king then?” Jesus answered, “You say that I am a king. For this reason I have been born, and for this reason I have come into the world, that I should testify to the truth. Everyone who is of the truth listens to my voice.”

Thanks for reading. He is!