Proverbs 20:19 in the King James Version
He that goeth about as a talebearer revealeth secrets: therefore meddle not with him that flattereth with his lips.
Context
18 Plans are established by advice; by wise guidance you wage war!
19 He who goes about as a tale-bearer reveals secrets; therefore don’t keep company with him who opens wide his lips.
20 Whoever curses his father or his mother, his lamp shall be put out in blackness of darkness.