Job has had enough of his tormenting comforters (Job 16:2 f.). He could, if the positions were reversed, well enough offer them such mere verbal consolation (the stress in Job 16:5 is on mouth and lips). Translate Job 16:5 as a continuation of Job 16:4. I could strengthen you with my mouth, and my lip's compassion I would not spare (the last clause after LXX).

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