The Torah states regarding a Hebrew servant: "then his wife shall go out with him." Rabbi Yitzchak read this verse and asked a brilliantly simple question that exposed a deeper legal teaching hidden beneath the surface.
"Who brought her in," Rabbi Yitzchak demanded, "that Scripture needs to take her out?" The wife was never sold into servitude. She was never acquired by the master. She entered no legal obligation to the household. She is a free woman married to a man who happens to be a servant. So why does the Torah bother to state that she "goes out" with her husband when he is freed? You cannot exit a place you never entered.
The answer transforms the verse from a statement about departure into a statement about obligation. The phrase "his wife shall go out with him" is not really about the wife leaving. It is about what happened during the years of servitude. The Torah is telling us, retroactively, that while the husband served his master, the master was responsible for feeding and sustaining the servant's wife as well.
She "goes out with him" because, in a legal sense, she was "in" — she was included in the master's household obligations for the entire duration of her husband's service. The master could not simply acquire a servant's labor while leaving the servant's family to starve. The purchase of a servant's work carried with it the duty to support his dependents.
Rabbi Yitzchak's question — four words of sharp logic — revealed an entire framework of social welfare embedded in a single verse about a wife walking out a door.