[Jesus] gave himself for us to redeem us from all lawlessness and to purify for himself a people for his own possession who are zealous for good works.
Good works is everything that a believer expresses, achieves, undertakes, performs, or accomplishes because Christ lives in them. Good works cannot achieve right standing before God. However, a faith-filled salvation will produce many good works. Good works are the fruit of salvation, not its cause or basis. Good works flow from Christ’s grace enabling us to pour out costly love for and on behalf of others.
Being right with God is by faith alone, but not by a faith that stands alone. No place exists in the Christian life for claiming a “born from above” experience while displaying no evidence of a changed life. A born-again life is a life that allows Christ to live in and through us dispensing the fruit of the Spirit openly and widely (1 John 4:9).
Good works are described as the fruit of faith. Good works are not produced by the Christian, but good works are borne in the life of the Christian by the Holy Spirit (Gal. 5:22-23). We are fruit-bearers not fruit-producers: enabling grace works out the life of Christ in us.
Good works, or deeds, display to the world the changed heart that Christ has created in us (Matt. 7:15-20). Faith in the finished work of Christ expresses itself in deeds done for God and others. Good works are the fruit of faith, they follow after justification, they are evidence of a changed heart, and therefore, flow from a heart transformed by the Cross.
In the end, Martin Luther’s old formula still sums things up nicely: “We are saved by faith alone [not our works], but not by a faith that remains alone.” Nothing we can do merit God’s grace and favor, we can only believe that he has given it to us in Jesus Christ and receive it by faith. But if we truly believe and trust in the one who sacrificially served us, it changes us into people who sacrificially serve God and our neighbors. If we say “I believe in Jesus” but it doesn’t affect the way we live, the answer is not that now we need to add hard work to our faith so much as that we haven’t truly understood or believed in Jesus at all.
Timothy Keller, The Prodigal God : Recovering the Heart of the Christian Faith (New York: Dutton, 2008), 123.