אָר֕וּר מַכֵּ֥ה רֵעֵ֖הוּ בַּסָּ֑תֶר וְאָמַ֥ר כָּל־הָעָ֖ם אָמֵֽן׃ (ס)
Cursed be he that smiteth his neighbour in secret. And all the people shall say: Amen.
Targum Jonathan on Deuteronomy
Accursed is he who attacketh his neighbour with slander in secret. And all shall answer together, and say, Amen.