“O generation of vipers, how can ye, being euil, speake good things? For out of the abundance of the heart the mouth speaketh.”
1611 King James Version (KJV)
12:34 In another kind likewise, the tree is known by its fruit - Namely, the heart by the conversation.
Mt 12:34,35 Generation of vipers. Poisonous, evil and dangerous, like vipers. How can ye, etc.? Their hearts were thoroughly evil, hence they could only speak and do evil, for "out of the good treasure of the heart the mouth speaketh". On the other hand, the "good man out of the good treasure of his heart bringeth forth good things".