There are two sides to salvation. The divine side which is grace and the human side which is obedient faith. Evangelicals argue that if one "works" for salvation then the reward is paid in wages rather than a gift. This is an over-simplification. God gives us food, but we must work for it. God gave Joshua the city of Jericho, but he was still commanded to march around the walls for seven days (Joshua 6:2,4). Likewise salvation is the free gift of God, but man must comply with the conditions.

Ron Abel, Wrested Scriptures, page 160