Romans 6:6

We know that our old self (our human nature without the Holy Spirit) was nailed to the cross with Him, in order that our body of sin might be done away with, so that we would no longer be slaves to sin.

God gave us armor to protect ourselves against enemies’ attacks. The adversary’s job is to find weaknesses to drag us back from faith. Our knowledge of the word is necessary because we speak the word to counter the enemy just as Jesus did when He was tried. We are no longer slaves of sin; the Word is our sword.