Matthew Henry on Judges 21:16–end
We have here the method that was taken to provide the 200 Benjamites that remained with wives. And, though the tribe was reduced to a small number, they were only in care to provide each man with one wife, not with more under pretence of multiplying them the faster. They may not bestow their daughters upon them, but to save their oath, and yet marry some of their daughters to them, they put them into a way of taking them by surprise, and marrying them, which should be ratified by their parents' consent, ex post facto - afterwards. The less consideration is used before the making of a vow, the more, commonly, there is need of afterwards for the keeping of it.
I. That which gave an opportunity…
Read the whole note in the consoleJamieson-Fausset-Brown on Judges 21:16
THE ELDERS CONSULT HOW TO FIND WIVES FOR THOSE THAT WERE LEFT. (Jdg 21:16-21)
the elders of the congregation said, How shall we do for wives for them that remain--Though the young women of Jabesh-gilead had been carefully spared, the supply was found inadequate, and some other expedient must be resorted to.
John Gill on Judges 21:16
Then the elders of the congregation said.... This being the case, that there were not wives enough for them, they were obliged to consult again, and consider of another expedient to provide for them; and this motion came from the elders of the people, not only in years, but in office:
how shall we do for wives for them that remain: the other two hundred, who had none:
seeing the women are destroyed out of Benjamin? and so no wives to be had there; and as for the Israelites which came to Mizpeh, who were of all the tribes of Israel, they had solemnly sworn that they would not give any of their daughters to them, and therefore it was a very difficult thing to provide wives for them.
Keil & Delitzsch on Judges 21:15-16
Of the six hundred Benjaminites who had escaped, there still remained two hundred to be provided with wives. To these the congregation gave permission to take wives by force at a festival at Shiloh. The account of this is once more introduced, with a description of the anxiety felt by the congregation for the continuance of the tribe of Benjamin. Jdg 21:15, Jdg 21:16, and Jdg 21:18 are only a repetition of Jdg 21:6 and Jdg 21:7, with a slight change of expression. The "breach (perez) in the tribes of Israel" had arisen from the almost complete extermination of Benjamin. "For out of Benjamin is (every) woman destroyed," viz., by the ruthless slaughter of the whole of the people of that tribe…