The Flesh Nature Must Be Put to Death
"That ye put off concerning the former conversation the old man, which is corrupt according to deceitful lusts; and be renewed in the spirit of your mind; and that ye put on the new man, which after God is created in righteousness and true holiness" (Eph 4:22-24). The purpose of the cross of Christ was not that we should continue to live in sin, but that we should die to sin. "Who His own self bare our sins in His own body on the tree, that we, being dead to sins, should live unto righteousness" (1 Pet. 2:24). Righteousness is walking right in God's eyes by obeying His commandments.
When we love the flesh, we have our minds set on earthly things. When we love Jesus with all our hearts, we lay down our lives on this earth, because our minds (interests) are set on things above.
Jesus explained how we lay down our lives in John 12:24, 25: "Except a corn of wheat fall into the ground and die, it abideth alone: but if it die, it bringeth forth much fruit. He that loveth his (fleshly) life shall lose it (because of the judgment of the law); and he that hateth his life in this world shall keep it unto life eternal." This is how we overcome the powers of darkness. If you have laid down your life in this world, the powers of darkness have nothing with which to tempt you. Jesus said, "For the prince of this world cometh, and hath nothing in me (my flesh)" (John 14:30). "And they overcame him (the devil) by the blood of the Lamb... and they loved not their lives unto the death" (Rev. 12:11).