Matthew 12:33-37 "Either make the tree good and its fruit good, or else make the tree bad and its fruit bad; for a tree is known by its fruit. Brood of vipers! How can you, being evil, speak good things? For out of the abundance of the heart the mouth speaks. A good man out of the good treasure of his heart brings forth good things, and an evil man out of the evil treasure brings forth evil things. But I say to you that for every idle word men may speak, they will give account of it in the day of judgment. For by your words you will be justified, and by your words you will be condemned."
Jeremiah 17:9 " The heart is deceitful above all things, And desperately wicked; Who can know it?
Matthew 15:18-19 But those things which proceed out of the mouth come from the heart, and they defile a man. For out of the heart proceed evil thoughts, murders, adulteries, fornications, thefts, false witness, blasphemies.
Proverbs 23:7 For as he thinks in his heart, so is he. " Eat and drink!" he says to you, But his heart is not with you.
Proverbs 4:23 Keep your heart with all diligence, For out of it spring the issues of life.
Philippians 4:8 Finally, brethren, whatever things are true, whatever things are noble, whatever things are just, whatever things are pure, whatever things are lovely, whatever things are of good report, if there is any virtue and if there is anything praiseworthy—meditate on these things.
Hebrews 4:12 For the word of Godis living and powerful, and sharper than any two-edged sword, piercing even to the division of soul and spirit, and of joints and marrow, and is a discerner of the thoughts and intents of the heart.
Exodus 20:17 "You shall not covet your neighbor's house; you shall not covet your neighbor's wife, nor his male servant, nor his female servant, nor his ox, nor his donkey, nor anything that is your neighbor's."
1 Samuel 16:7 But the LORD said to Samuel, “Do not look at his appearance or at his physical stature, because I have refused him. For the LORD does not see as man sees; for man looks at the outward appearance, but the LORD looks at the heart.”
1 Kings 11:1-6 But King Solomon loved many foreign women, as well as the daughter of Pharaoh: women of the Moabites, Ammonites, Edomites, Sidonians, and Hittites— from the nations of whom the LORD had said to the children of Israel, "You shall not intermarry with them, nor they with you. Surely they will turn away your hearts after their gods." Solomon clung to these in love. And he had seven hundred wives, princesses, and three hundred concubines; and his wives turned away his heart. For it was so, when Solomon was old, that his wives turned his heart after other gods; and his heart was not loyal to the LORD his God, as was the heart of his father David. For Solomon went after Ashtoreth the goddess of the Sidonians, and after Milcom the abomination of the Ammonites. Solomon did evil in the sight of the LORD, and did not fully follow the LORD, as did his father David.