From the 《尚书·汤诰》: 「尔万方百姓罹其凶害, 弗忍荼毒」 ('the people of all regions suffer his cruelty, unable to bear his torments') — the speech in which Tang the Successful denounces the tyrant Jie. Anchored as classical-flavored vocabulary ever since.
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Literary / formal — common in editorials, history writing, and rhetoric ('荼毒生灵' = 'torment all living things'). Don't use it in casual conversation.