Reference for Gittin 134:18

רב יוסף איעסק בריחיא רב ששת איעסק בכשורי אמר גדולה מלאכה שמחממת את בעליה

and his flesh was covered with bright spots. R. Joseph used to cure the shivers by working at the mill, R. Shesheth by carrying heavy beams. He said: Work is a splendid thing to make one warm.<span class="x" onmousemove="('comment',' Lit., 'to make warm its master'. ');">¹⁵</span>

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