Ephesians 6:11 : "Put on the full armor of God so that you can take your stand against the devil’s schemes." Satan and demons can cause a lot of trouble (just look at the world!). They can hurt people's bodies, minds, relationships, futures, etc. They delight in causing people to hurt others, self-destruct, commit crimes, or engage in any of "the acts of the sinful nature ... sexual immorality, impurity and debauchery; idolatry and witchcraft; hatred, discord, jealousy, fits of rage, selfish ambition, dissentions, factions, and envy, drunkenness, orgies, and the like" ( Gal. 5:19-23 ). They incite "wickedness, evil, greed, and depravity ... murder, strife and malice," and tempt people to become godless, truth-suppressors, thankless, foolish, dark-hearted, idol/nature-worshippers, perverted, depraved, gossips, slanderers, God-haters, insolent, arrogant, boastful, inventors of new ways to do evil, disobedient, senseless, faithless, heartless...