English: Rabbi Meir says: Any condition that is not like the condition of the children of Gad and the children of Reuven is not a valid condition. And so it is written “And if the woman is not willing to follow you, then you shall be clear of this oath of mine.”
On the daf / in context: Kiddushin 61a requires that a conditional obligation state both the positive and the negative clauses (as in the Gad/Reuven arrangement). Avraham’s wording to Eliezer supplies an early model of a properly doubled condition.
Type of Learning
Custom (Bavli — form of a valid condition, R’ Meir)
What Is Learned
A binding condition must state both the affirmative and the negative outcomes, following the pattern of the tribes of Gad and Reuven and of Avraham’s release of Eliezer if the woman refuses.