Both a person who took an oath in private and one who took one in public - even one who took an oath in God's ineffable name, [swearing] by God, the Lord of Israel - may appeal for a release of his oath if he changes his mind.
If, however, one took an oath or a vow based on the understanding of many others, it may not be released except for a purpose associated with a mitzvah.
And the Rabbis, who hold that such a vow can also be dissolved, respond to this claim in the following manner: There, did the oath take effect with regard to them at all? Since the people of Gibeon said to them: “We came from a far country” (Joshua 9:6), and they did not come from a far country, the oath did not take effect with regard to the Jewish people at all, as it was taken under false pretenses. And this, that the Jewish people did not kill the Gibeonites, like they did to the other nations who resided in the land of Canaan, despite the fact that the vow did not take effect, was due to the sanctity of God’s name. If they would have killed them, they would have desecrated God’s name by not fulfilling their word, although this vow did not take effect.
The Gemara asks: And how many people constitute the public with regard to this halakha? Rav Naḥman says: Three people. Rabbi Yitzḥak says: Ten people. The Gemara explains their opinions.
“And the children of Israel did not smite them, for the princes of the assembly had sworn to them” (Joshua 9:18), and since this oath was uttered in the presence of many people, it could not be rescinded, although it was undertaken in error because the Gibeonites had deceived the people of Israel. The Gemara poses a question: And how many people are considered many for the purposes of this law? Rav Naḥman bar Yitzḥak said: Three, as can be learned from the laws of a woman who experiences a discharge of uterine blood after her menstrual period [zava]: “Days” indicates two, which is the minimal number justifying use of the plural noun. The term “many days” (Leviticus 15:25) therefore indicates a total of three. Rabbi Yitzḥak said: Ten, as the term “assembly” is written in relation to the Gibeonites, and it is taught elsewhere that an assembly is comprised of at least ten members.
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Rav Naḥman disagreed with Rav Huna and said: Even if she married again, the orphans can have the court administer a vow to the widow. The Gemara asks: If she married, then her husband will certainly nullify this vow. The Gemara answers that we, the court, administer the vow in public, and therefore her husband cannot nullify the vow.
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