Jeremiah 17:9
"The heart is deceitful above all things, and desperately wicked: who can know it?"
Cross References (ranked by relevance)
For out of the heart proceed evil thoughts, murders, adulteries, fornications, thefts, false witness, blasphemies:
This is an evil among all things that are done under the sun, that there is one event unto all: yea, also the heart of the sons of men is full of evil, and madness is in their heart while they live, and after that they go to the dead.
He that trusteth in his own heart is a fool: but whoso walketh wisely, he shall be delivered.
Take heed, brethren, lest there be in any of you an evil heart of unbelief, in departing from the living God.
And God saw that the wickedness of man was great in the earth, and that every imagination of the thoughts of his heart was only evil continually.
And the LORD smelled a sweet savour; and the LORD said in his heart, I will not again curse the ground any more for man’s sake; for the imagination of man’s heart is evil from his youth; neither will I again smite any more every thing living, as I have done.
For this people’s heart is waxed gross, and their ears are dull of hearing, and their eyes they have closed; lest at any time they should see with their eyes and hear with their ears, and should understand with their heart, and should be converted, and I should heal them.
And ye have done worse than your fathers; for, behold, ye walk every one after the imagination of his evil heart, that they may not hearken unto me:
Behold, I was shapen in iniquity; and in sin did my mother conceive me.