שָֽׁנֲנ֣וּ לְשׁוֹנָם֮ כְּֽמוֹ־נָ֫חָ֥שׁ חֲמַ֥ת עַכְשׁ֑וּב תַּ֖חַת שְׂפָתֵ֣ימוֹ סֶֽלָה׃
They have sharpened their tongue like a serpent; Vipers' venom is under their lips. Selah
Read Jewish philosophical commentary on Psalms 140:4: and classical philosophical sources.