1 John 4:4

Little children (believers, dear ones), you are of God and you belong to Him and have (already) overcome them (the agents of the antichrist); because He who is in you is greater than he (Satan) who is in the world (of sinful mankind).

We must study until we believe. Our minds are exposed to negative bombardments every day until it wears our faith down. The Word builds us back up to carry our sword daily.  If the devil can get us to not stand on the authority of our word we will be defeated in doubt. We have the power of God living on the inside of us and can flatten the opposition of the enemy. Are we using it?