The Wikipedia has a license, which allows copying, such as this, as I understand it. I had occasion to look for some ideas on the topic of Grace, and decided to try that source. I am not a theologian, but I was impressed with the article on Divine Grace, as I found it on June 3, 2005. (It may be different next time I look. You may decide to edit the article yourself. Get a login, learn a little about what to do, and start participating in writing an encyclopedia!) Here are some excerpts:
Divine grace is a Christian term for gifts granted to humanity by God, that God is under no need or obligation to grant. Most broadly, grace describes all of God's gifts to humankind, including our life, creation, and salvation, which God gives to us freely. More narrowly but more commonly, grace describes the means by which humans are saved from original sin and granted salvation. This latter concept of grace is of central importance in the theology of Christianity . . .
Most Christians of any of the major Western denominations agree that mankind is born in a state of sin. This is a consequence of original sin; a sinful nature is inherited; it is part of man's condition. Traditionally, original sin is explained as a result of the fall of man through the first sins of Adam and Eve in Eden. Some would now reject the story from Genesis as history. But even those who reject it still agree that men are born in sin. The original state of grace enjoyed by the once-good people God created has been lost, for them and for their descendants. We are born having forfeited any claim to salvation. (By contrast, Eastern Orthodoxy does not subscribe to this particular doctrine of original sin.)
God's grace responds to this otherwise hopeless situation. God, at His initiative, sent prophets and other teachers to reveal His existence to mankind. He gave the Torah, the Law of Moses, to the Jews, and made them his chosen people to provide a moral example to the rest of mankind.
It was also through the Jews that God's grace sent his Son, Jesus Christ, who sought to make atonement for the sins of mankind through his crucifixion and subsequent resurrection. God's grace is freely given, on behalf of the men He has called to salvation. God was not obliged to save anyone; men cannot make themselves good enough to earn their way into Heaven on their own initiative, or give rise to a duty on God's part to save them. It is only through the redemption bought by Christ's sacrifice that anyone is saved, and the path of salvation for men lies in participating in that redemption. Indeed, some denominations of Christianity paraphrase grace as "God's Rewards At Christ's Expense" to represent this.
Grace, then, is God's initiative and choice to make a path of salvation available for men. On this, almost all Christians agree, though they may disagree on the meaning of some terms, or on which parts of the narrative of grace to emphasize.
That's just part of the article. There's quite a bit more. Read it for yourself.