If anyone thinks himself to be religious, yet does not bridle his tongue but deceives his own heart, this person’s religion is worthless.
He feeds on ashes; a deceived heart has misled him. And he cannot save himself, nor say, “Is there not a lie in my right hand?”
“The heart is more deceitful than all else and is desperately sick; Who can understand it?
I, the Lord, search the heart, I test the mind, To give to each person according to his ways, According to the results of his deeds.
But one who has looked intently at the perfect law, the law of freedom, and has continued in it, not having become a forgetful hearer but an active doer, this person will be blessed in what he does.
The good person out of the good treasure of his heart brings forth what is good; and the evil person out of the evil treasure brings forth what is evil; for his mouth speaks from that which fills his heart.
But prove yourselves doers of the word, and not just hearers who deceive themselves.
(James 1:26, Isaiah 44:20, Jeremiah 17:9-10, James 1:25, Luke 6:45, James 1:22)