[Avodah] Was Ben Petura a Christian?

[L Reich]

The Talmud tells us


"Two people were traveling, and [only] one of them had a canteen of 
water.[There was only enough water so that] if both of them drank they would 
both die, but if one of them drank [only] he would make it back to an 
inhabited area [and live].Ben Petura publicly taught:'Better both should 
drink and die than that one see his friend's death,' until Rabbi Akiva came 
and taught: 'Your brother should live with you' (Vayikra 25:36) - your life 
takes precedence over the life of your friend's.'" (Bava Metzia62a).


I have a vague memory of reading somewhere that Ben Petura was not a Tanna, 
but a Christian.

Can anyone cast light on this?

Elozor Reich