Néder és korbán

GEMARA: The Gemara inquires about Rabbi Eliezer’s suggestion to instruct the minor to refuse: Is it permitted to instruct her to refuse? Doesn’t bar Kappara teach: A person should always cling to three things and distance himself from three things. He should cling to three things: To ḥalitza rather than levirate marriage, to bringing about peace, and to the nullification of vows. And he should distance himself from three things: From refusal; and from accepting deposits, as he is then responsible for them; and from serving as a guarantor. The Gemara answers: A refusal for a mitzva is different, as this refusal is performed to allow the mitzva of levirate marriage to be fulfilled with the other sister.

We also do not broach dissolution using this other method, as it is taught in a baraita: Rabbi Natan says: One who vows is considered as if he built a personal altar outside the Temple, which is prohibited, and one who fulfills this vow is considered as if he sacrifices an offering on it. With the first clause, we may broach dissolution by informing the one who vowed that vowing is akin to building an altar outside the Temple, but with regard to the latter clause there is a dispute among the Sages. Abaye said: We do broach dissolution by telling someone that fulfilling a vow is like sacrificing an offering on a forbidden altar, while Rava said: We do not broach dissolution with it.

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