Leviticus 12:5

But if she bear a maid child. — Better, but if she giveth birth to a female child. (See Leviticus 12:2.)

As in her separation. — Better, as in the time of her monthly courses. (See Leviticus 12:2.) In the case of a daughter the days of purification in both stages is exactly double that prescribed at the birth of a son. The reason for this difference is probably owing to the fact that the ancients believed that the physical derangement of the system is far greater at the birth of a girl than at the birth of a boy, and that it requires a longer time for the effects to pass away. Similar laws obtained among other nations of antiquity, and exist to this day among many Eastern tribes. The Greeks held that the man who had been near a woman in childbirth defiled the altar if he approached it. One of the means adopted during the Peloponnesian war for purifying the island of Delos was to proscribe women keeping their confinement on the island. The Hindoos go so far as to regard all the relations of a new-born child as impure; the father has to undergo lustrations, and the mother remains unclean till the tenth day, when the child receives its name. Among the Arabs the mother continues unclean for forty days.

In the blood of her purifying. — Better, in the blood of purification, that is, pure blood. (See Leviticus 12:4.) It will be seen that the law here only legislates for ordinary cases, and that it passes over in silence cases of twins. The administrators of the law during the second Temple had therefore, in this instance, as in many other points, to supplement the Mosaic legislation. They therefore enacted that when a mother had twins, and if they were a boy and a girl, the two stages of her uncleanness were those for a girl. If one of the twins was a boy and the other sexless, or bi-sexual, she continued unclean for both male and female. If, on the contrary, one was a female and the other of neither sex, or bi-sexual, her separation was only for a female.