תִּטְחַ֣ן לְאַחֵ֣ר אִשְׁתִּ֑י וְ֝עָלֶ֗יהָ יִכְרְע֥וּן אֲחֵרִֽין׃
그리하였으면 내 처가 타인의 매를 돌리며 타인이 더불어 동침하는 것이 마땅하니라
Rashi
may my wife grind for someone else Our Sages explained this as an expression of sexual intercourse, as in (Jud. 16:21), “and he did grind in the prison house.”