Then the elders of that city shall take the man and punish him.
18. And the elders of that city shall take that man. Calumny in this case received a threefold punishment; first, that he, who had invented the false accusation, should be beaten with stripes; secondly, that he should pay an hundred pieces of silver to the father of the girl; thirdly, that he should never be allowed to put her away; and tie reason is given...
These laws relate to the seventh commandment, laying a restraint by laying a penalty upon those fleshly lusts which war against the soul. I. If a man, lusting after another woman, to get rid of his wife slander her and falsely accuse her, as not having the virginity she pretended to when he married her, upon the disproof of his slander he must be punished, Deu 22:13-19.
Commenting on Deuteronomy 22:13-30
And they shall amerce him in an hundred shekels of silver,.... Which was about twelve pounds of our money; this was double the dowry he would have been obliged to have given her, if he had put her away; which he might have done with less trouble, and with a greater certainty of being rid of her; but being willing to save that expense, took...