Exodus 21:7

If a man sell his daughter - This the Jews allowed no man to do but in extreme distress - when he had no goods, either movable or immovable left, even to the clothes on his back; and he had this permission only while she was unmarriageable. It may appear at first view strange that such a law should have been given; but let it be remembered, that this servitude could extend, at the utmost, only to six years; and that it was nearly the same as in some cases of apprenticeship among us, where the parents bind the child for seven years, and have from the master so much per week during that period.

A man might, in accordance with existing custom, sell his daughter to another man with a view to her becoming an inferior wife, or concubine. In this case, she was not "to go out," like the bondman; that is, she was not to be dismissed at the end of the sixth year. But women who were bound in any other way, would appear to have been under the same conditions as bondmen. See Deuteronomy 15:17.