A widow seized a Shifchah. The case came in front of R. Yitzchak. He said 'what you seized, you seized' (you keep her).

R. Imi took [the Shifchah] from her, for she thought that [the Shifchah] is hers, and she is not hers.

This is like the case of the sons of Shamai. Their father died, and he left to them a goat. A creditor came and took it. The case came in front of R. Avahu. He said 'he took his own' (he seized properly).

Question: Was it not taught that an heir and a creditor - if one of them preempted and seized, we take from him!

Answer: [That is when they seized mistakenly -] they thought that they are theirs, and they are not theirs. (We explained this like PNEI MOSHE.)

(R. Yakov bar Zavdi): R. Avahu agrees that if [the heirs] sold [the goat], gave it for collateral or moved it from place to place, and afterwards the creditor came and seized it, we take from him (for the heirs acquired it).

Question: Exert yourself [and you will find the answer! If the widow or creditor] is exempt from a Shevu'ah [what will R. Akiva say]?

Answer: [Even so the heirs get it, for inheritance] is Torah law, and this (a widow or creditor collecting from heirs) is not Torah.