Keep thy heart with all diligence; for out of it are the issues of life.
Matthew 5:8Blessed are the pure in heart: for they shall see God.
Matthew 5:28But I say unto you, That whosoever looketh on a woman to lust after her hath committed adultery with her already in his heart.
Galatians 5:16This I say then, Walk in the Spirit, and ye shall not fulfil the lust of the flesh.
Philippians 4:8Finally, brethren, whatsoever things are true, whatsoever things are honest, whatsoever things are just, whatsoever things are pure, whatsoever things are lovely, whatsoever things are of good report; if there be any virtue, and if there be any praise, think on these things.