What does 'destroyed' mean when the Bible says the body of sin is destroyed?
Destroyed in that phrase does not mean removed or annihilated. In the Greek it means knocked out of commission; the body of sin, or old Adam, has lost its power. It is like a main fuse pulled: lights go out, but power remains and can be restored. Believers should no longer serve old Adam.
Les explains that the body of sin is the old Adam, crucified with Christ. He says the Greek word rendered 'destroyed' does not mean removed or annihilated; it means knocked out of commission, so it has lost its power. Les illustrates this with a main fuse box: pulling the lever turns off the lights, but the power is still there and can be flipped back on. That is what happened to the old Adam—he lost his power—so henceforth we should not serve old Adam. The unbeliever, by contrast, is living to satisfy the desires of old Adam. This identification is received by faith, not feeling or experience.