מָ֣וֶת וְ֭חַיִּים בְּיַד־לָשׁ֑וֹן וְ֝אֹהֲבֶ֗יהָ יֹאכַ֥ל פִּרְיָֽהּ׃
Death and life are in the power of the tongue; And they that indulge it shall eat the fruit thereof.
Read kabbalistic (mystical) interpretation of Proverbs 18:21: and classical mystical sources.