The Bible says in 1 Peter 1:14-16: As obedient children, not fashioning yourselves according to the former lusts in your ignorance: 15But as he which hath called you is holy, so be ye holy in all manner of conversation; 16Because it is written, Be ye holy; for I am holy.
The apostle Peter, in 1 Peter 5:8, Also warns us of the devil’s power when he says, Be sober, be vigilant; because your adversary the devil, as a roaring lion, walketh about, seeking whom he may devour.