Verse 1:[1] Now (Judg. 20:1) the men of Israel had sworn in Mizpeh, saying, There shall not any of us give his daughter unto Benjamin to wife.
[They had sworn] They had sworn (Bonfrerius, similarly Junius and Tremellius), that is, before the beginning of the war, Judges 20:1. Evidently for the fuller detestation of the deed (Junius). Hebrew: he was sworn,[2] that is, he swore. Thus, he was sworn unto the Voconain law[3] (Drusius).
[No one…shall give…a wife] That that had treated the wife of the Levite so savagely are unworthy to have wives from us (Malvenda). They held them in the place in which הַמְּנוּדִים, the excommunicated, who, having been removed from the synagogue, were not able to contract marriages with others (Drusius). Question: Whether this oath was lawful, and brought obligation? Response: Some answer in the negative (thus Tostatus, Martyr). This oath was neither pious nor lawful, and so it did not obligate. Thus it was necessary that the Benjamites either take foreign wives, which was forbidden by the Law; or to remain perpetually unmarried, and thus that Tribe would utterly perish (Martyr); and at the same time they would be exposed to the danger of harlotry (Tostatus). [But these reasons are not satisfying to Bonfrerius.] If any evil followed from this matter, it had been by accident: just as, if any city should be anathematized, they ought not on account of that to abstain from inflicting punishment, because they have credible intelligence that many are going to kill themselves out of desperation. Neither is it evident that God willed in no manner to anathematize whole Tribes, if they had admitted grievous scandal, when He subjected entire cities to anathema, Deuteronomy 14, and He led away the ten Tribes, etc. What Tostatus supposes is not plausible, that there was such ignorance among all the people and Phinehas, that they did not know this oath to be unlawful. Therefore, I say that this oath was both rightly conceived, and rightly kept, by the Israelites; nevertheless, it did not include that case of extreme necessity, namely, that a Tribe might be extinguished, or come to other extreme inconveniences (Bonfrerius). Afterwards consulting God on this account, they did not obtain liberty from the vow, but they did learn a way to fulfill the vow, and to preserve the Tribe. In this manner God demonstrated just how much He values both, the religion of the vow, and the salvation of the people (Malvenda out of Junius). Moreover, we learned from this passage that it was not lawful for daughters to marry without the consent of parents; otherwise someone would have said, Even if you are unwilling to give your daughters to them, your daughters by their own will will give themselves to them, etc. (Martyr).
The men of Israel had sworn; in the beginning of this war, after the whole tribe had espoused the quarrel of the men of Gibeah, Judges 20:13, 14. They do not (as some suppose) here swear the utter extirpation of the tribe, which fell out beyond their expectation, Judges 21:3, 6, but only not to give their daughters to those men who should survive; justly esteeming them for their barbarous villany to be as bad as the worst of heathens, with whom they were forbidden to marry. In this case the Benjamites might have married among themselves, if any of their men and women were left alive.
[1] Hebrew: וְאִ֣ישׁ יִשְׂרָאֵ֔ל נִשְׁבַּ֥ע בַּמִּצְפָּ֖ה לֵאמֹ֑ר אִ֣ישׁ מִמֶּ֔נּוּ לֹא־יִתֵּ֥ן בִּתּ֛וֹ לְבִנְיָמִ֖ן לְאִשָּֽׁה׃
[2] Hebrew: נִשְׁבַּע, in the Niphal (passive) conjugation.
[3] Cicero’s Pro Sulla 34. Quintus Voconius Saxa was a plebian tribune in 169 BC. In that year a law was enacted concerning the right of women to inherit.