Why can't salvation be earned by works if it is called a gift?
Salvation cannot be earned by works because Scripture contrasts wages with a gift. Romans 6:23 says the wages of sin is death, but the gift of God is eternal life through Jesus Christ. A gift ceases to be a gift the moment someone works for it, so salvation must be received entirely as God's gift, without any work.
Les teaches that Romans 6:23 literally blows out of the saddle the idea that salvation must be worked for. The verse says the wages of sin is death—spiritual death—which is something earned. But the other side is that the gift of God is eternal life through Jesus Christ our Lord. Les then asks how much work a person can do and still call it a gift; the answer is none. You cannot work for something and then call it a gift. As soon as you work for it, it is no longer a gift, and so it is with salvation. It must be taken totally as a gift of God without having to do any work of any kind. He also notes there are areas of reward that believers should work for, but salvation itself is not earned.
For the wages of sin is death; but the gift of God is eternal life through Jesus Christ our Lord.
More Questions
What is the difference between wages and a gift in salvation?
The difference between wages and a gift is that wages are what you deserve, while a gift is something you do not deserve.