Paul says Practice What You Preach

And art confident that thou thyself art a guide of the blind, a light of them which are in darkness, An instructor of the foolish, a teacher of babes, which hast the form of knowledge and of the truth in the law. Thou therefore which teachest another, teachest thou not thyself? thou that preachest a man should not steal, dost thou steal? Thou that sayest a man should not commit adultery, dost thou commit adultery? thou that abhorrest idols, dost thou commit sacrilege? Thou that makest thy boast of the law, through breaking the law dishonourest thou God? Romans 2:19-23