Reference for Bava Kamma 193:4

אלא הכא מי ניחא ליה דנכחוש עבדיה אמרי ה"נ ניחא ליה דלא ליסתרי עבדיה

with a case [where he took hold of the slave at a time] when [the owner] usually required no work from him, exactly as R. Abba sent to Mari b. Mar, saying. 'Ask R. Huna whether a person who stays in the premises<span class="x" onmousemove="('comment',' [Which the owner is not accustomed to let — a case similar to the one where the owner requires no work from the slave.] ');">⁴</span>

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