An Etymological Dictionary of the German Language/Annotated/Ruhe
Appearance
Ruhe, feminine, ‘rest, repose, calm, peace,’ from the equivalent Middle High German ruowe, Old High German ruowa, feminine (also Middle High German râwe, Old High German râwa, in the same sense); compare Old Icelandic ró, Anglo-Saxon rôw, feminine, ‘rest.’ Gothic *rôwa (with the graded form *rêwa) corresponds exactly to Greek ἐ-ρωή, ‘desisting, ceasing, rest,’ from Aryan rôwâ; the root rô contained in these words is probably allied to ra- in Modern High German Rast; yet the East Middle German Ruge used by Luther presents a difficulty. —