R. Yitzchak of Dahavan had slaves. They fled to villages. He asked R. Imi. He ruled for him that Oni is forbidden (a document that says 'when you flee from him, I have claim on you.' This is like freedom, and one may not free slaves without need.) Antaris (a temporary sale, for while he is in Chutz la'Aretz) is permitted. Afarkorim requires investigation (a Stam sale document. Perhaps it is permitted, for it is clear that he sells only because they fled, and when he returns to Eretz Yisrael, the sale is Batel.

The Shifchah of R. Aba bar Ada fled to Kalisiya. He came and asked R. Mana, and they ruled for him like R. Imi, that Oni is forbidden, Antaris is permitted, and Afarkorim requires investigation.

We do not redeem captives for more than their value, due to for Tikun ha'Olam. And we do not help captives escape, due to Tikun ha'Olam. R. Shimon ben Gamliel says, this is to help captives.

This is lest [captors] be harsh [with other captives, and overly fetter them to prevent escape - PNEI MOSHE].

(Beraisa): One may not buy Sefarim, Tefilin or Mezuzos from a Nochri.

Question (Beraisa): A case occurred in which a Nochri in Tzidan sold Tefilin and Mezuzos, and the case came in front of Rabanan, and they said that one may buy from him!

Answer (R. Shmuel bar Nasan): That was a convert who reverted to be like a Nochri. (We did not ask from our Mishnah, which permits buying for their value, for that is when it is known that they were of a Yisrael. We forbid when it is possible that the Nochri himself wrote them - R. MEIR SIMCHAH.)