Psalms 50:19 KJV

Thou givest thy mouth to evil, and thy tongue frameth deceit.
Psalms 50:19, King James Version

In context

18 When thou sawest a thief, then thou consentedst with him, and hast been partaker with adulterers.

19 Thou givest thy mouth to evil, and thy tongue frameth deceit.

20 Thou sittest and speakest against thy brother; thou slanderest thine own mother’s son.