Ephesians 6:11-12

Put on the whole armor of God, that you may be able to stand against the wiles of the devil. For we do not wrestle against flesh and blood, but against principalities, against powers, against the rulers of the darkness of this age, against spiritual hosts of wickedness in the heavenly places.
—Ephesians 6:11-12, NKJV

Billy Graham said, “If you are a true believer in Christ, you are going to be at war. The flesh will fight against the spirit, and the spirit against the flesh, and there will be constant conflict. … Too many people want to have one foot in the world and one foot in the kingdom of God, and it is like straddling a fence. You are not happy either way. Declare yourself for Christ.”