and why.

Jeremiah 4:14
Wash the evil from your heart, O Jerusalem, so that you may be saved. How long will you harbor wicked thoughts within you?

Daniel 4:5, 19
I had a dream, and it frightened me; while in my bed, the images and visions in my mind alarmed me. . . .

Matthew 16:8
Aware of their conversation, Jesus said, "You of little faith, why are you talking among yourselves about having no bread?

Hebrews 4:13
Nothing in all creation is hidden from God's sight; everything is uncovered and exposed before the eyes of Him to whom we must give account.