Reference for Bava Metzia 189:12
במאי גמר אי במה מצינו איכא למיפרך כדפרכינן שכן אונס
And should you say, It is deduced from injury and death: [it might be argued,] as for these, [he is free] because they are unavoidable accidents? — But it follows from a paid bailee. And whence do we know it of a paid bailee himself? — The liability of a paid bailee is equated to that of a borrower: just as there, when the owner is lent for personal service, he [sc. the borrower] is free thereof, so here too [in the case of a paid bailee], when the owner is lent for personal service, he is free thereof. How is this deduced? If by analogy,<span class="x" onmousemove="('comment',' [H] Lit., 'what (do) we find?' i.e., as we find a paid bailee and a borrower responsible for certain mishaps, and we also find that the former ceases to be responsible when the owner of the bailment is personally in his service, so the same is assumed of the latter. ');"><sup>12</sup></span>