Ecclesiastes 10:20

Do not curse the king even in your thoughts, or curse the rich even in your bedroom, for a bird of the air may carry your words, and a winged creature may report your speech.

Curse not the king, no not in thy thought; and curse not the rich in thy bedchamber: for a bird of the air shall carry the voice, and that which hath wings shall tell the matter.

Note thought: or, conscience

Don’t curse the king, no, not in your thoughts; and don’t curse the rich in your bedroom, for a bird of the sky may carry your voice, and that which has wings may tell the matter.

Revile not the king, no, not in thy thought; and revile not the rich in thy bedchamber: for a bird of the heavens shall carry the voice, and that which hath wings shall tell the matter.