The Festivals of the Lord require sanctification by the court, as the Festival dates are established by the court’s determination of the New Moon, whereas Shabbat, which commemorates Creation, does not require sanctification by the court. Shabbat is sanctified every week independent of any court decision.

As for ben Azzai’s statement, it should be understood as follows: The Festivals of the Lord require an expert, as the start of the month, which is dependent upon the appearance of the new moon, which in turn determines the Festivals, can be established only by a court composed of experts. But the portion on vows does not require an expert, i.e., vows can be dissolved even by a court of laymen. This explanation of the baraita given to Rav Asi bar Natan also serves to explain Beit Shammai’s source for the halakha that three laymen can dissolve vows.

The Gemara raises a difficulty: But in the portion on vows the phrase “the heads of the tribes” (Numbers 30:2) is written. How, then, can it be said that vows can be dissolved by laymen? Rav Ḥisda said, and some say it was Rabbi Yoḥanan: From “the heads of the tribes,” the Sages derive that vows can be dissolved by a single expert by himself, but three laymen also have that ability.

§ Rabbi Ḥanina says: A husband who is silent and does not formally nullify his wife’s vow in order to annoy [lemeikat] her, but intends to nullify it later, can nullify it even from now until ten days later. Rava raised an objection to this from a baraita: When did they say that if the husband of a betrothed young woman dies, the authority to nullify the woman’s vows reverts to the father? The authority reverts to the father when the husband did not hear of her vow, or when he heard and was silent, or when he heard and nullified it and died on the same day. But if he heard and ratified it, or if he heard and was silent and died on the following day, he, the father, cannot nullify the vow.

What, is the phrase: Heard and was silent, not referring even to one who is silent in order to annoy her, and nevertheless nullification is only possible that day, contradicting the opinion of Rabbi Ḥanina? The Gemara answers: No, the baraita is referring to one who is silent in order to sustain the vow. The Gemara asks: If so, this is the same as: Or he heard and ratified, mentioned earlier in the baraita. Rather, the baraita is referring to one who is silent without any specific intent, as opposed to the husband who is silent in order to annoy his wife, whose intent is to nullify the vow.

Rav Ḥisda raised an objection from a different baraita: In some ways the halakha is more stringent in ratification than in nullification, and in other ways it is more stringent in nullification than in ratification. The stringency in ratification of vows is