1 Samuel 24:13

By the fruit of their lives you will know them. Do people gather grapes from thorn bushes, or figs from thistles?

Hence it is by the fruit of their lives that you will know such men.

You must assume either that both tree and fruit are good, or that both tree and fruit are worthless; since it is by it's fruits that a tree is known.

For out of the heart proceed evil thoughts--murder, adultery, unchastity, theft, perjury, slander.

Treasury of Scripture Knowledge

As saith the proverb of the ancients, Wickedness proceedeth from the wicked: but mine hand shall not be upon thee.

By the fruit of their lives you will know them. Do people gather grapes from thorn bushes, or figs from thistles?

You must assume either that both tree and fruit are good, or that both tree and fruit are worthless; since it is by it's fruits that a tree is known.

For out of the heart proceed evil thoughts--murder, adultery, unchastity, theft, perjury, slander.

But the things that come out from the mouth proceed from the heart, and it is these that defile a man;