(R. Ze'ira): This is when [the buyer and seller] do not sustain (say that they truly intended to vow), but if they sustain, they need a Heter through a Chacham.

Question: If [he vowed to two buyers, and] to this one he sustains (he intended for a Neder), and this one he does not sustain [what is the law]?

Answer: Since it is Batel for this one (to whom he does not sustain), it is Batel regarding this one. (A vow that is partially Batel is totally Batel.)

(Talmidim of R. Chiya bar Lulaini citing R. Yudan): If [the seller] said a Sela (four Zuz), and this [buyer] said to give to him for a Shekel, and [now the seller] said to give to him for three, he sustains (when he vowed, he did not intend to sell for less than three), since this one was Mevatel a Dinar to this one, he can be Mevatel another Dinar to him, and sell to him for two [if he wants. Even if he vowed with intent not to sell for less than three, this is Davar sheb'Lev (unspoken intent). He vowed about a Sela only to persuade, so it is Batel, and he never said a vow about three. We explained this like OHR SOMAYACH Hilchos Nedarim 4:3.]

(R. Ami): Who taught vows of persuasion? It is R. Tarfon (who says that Nezirus is only b'Hafla'ah (a clear acceptance), and he equates Nedarim to Nezirus).

[R. Ami] establishes our Mishnah when they sustain.

(R. Bari): It is like everyone, when they do not sustain.

Support: If you will say that it is when they sustain, it should teach that R. Eliezer ben Yakov and R. Tarfon both said the same matter!