English: “Your brother’s ox” — excluding the ox of a non-Jew.
On the daf / in context: The word “achikha” (your brother) is used to limit the biblical obligation of returning lost property to a fellow Jew (while later rabbinic enactments expand the scope for the sake of peaceful relations).
Type of Learning
Limiting derash (mi’ut) on the word “achikha”.
What Is Learned
The Torah’s positive commandment of returning a lost animal applies specifically to the property of a fellow Jew.