In Christianity, the belief that a person can achieve salvation only through faith and reliance on God's grace, not through good deeds. The phrase is adapted from a sentence in the epistles of Paul in the Bible: “By grace are ye saved through faith; and that not of yourselves: it is the gift of God.”
Note: Whether the actions of human beings can contribute to this justification, in addition to God's grace, was one of the great points of division among Christians at the time of the Reformation.