Matthew 12:34-38

You offspring of vipers, how can you, being evil, express any good things? For the mouth speaks from that which fills the heart.

The good person brings out of his good treasure good things; and the evil person brings out of his evil treasure evil things.

But I tell you that for every careless word that people speak, they will give an account of it on the day of judgment.

For by your words you will be justified, and by your words you will be condemned.” The Desire for Signs

Then some of the scribes and Pharisees said to Him, “Teacher, we want to see a sign from You.”