Reference for Bava Metzia 184:2

ואי אמרת משלו הוא אוכל בנו אמאי חייב אמר רבינא משום דמיחזי כמקח

[But if he stipulates, 'I accept the work] on condition that I and my son eat, or, 'that my son eat for my wage:'<span class="x" onmousemove="('comment',' Rashi: for the wage stipulated, so that he would draw no pay. Tosaf: instead of me. ');">²</span>

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