Neither shall thou lie with any beast, to defile thyself therewith,.... A female one, as Aben Ezra notes, as a mare, cow, or ewe, or any other beast, small or great, as Ben Gersom, or whether tame or wild, as Maimonides (b); and even fowls are comprehended, as the same writers observe:
neither shall any woman stand before a beast to lie down thereto: that is, stand before a beast, and by a lascivious and obscene behaviour solicit the beast to a congress with her, and then lie down after the manner of four-footed beasts, as the word signifies, that it may have carnal copulation with her: for a man to lie with a beast is most shocking and detestable, but for a woman to solicit such an unnatur…
Keil & Delitzsch on Leviticus 18:19-23
Prohibition of other kinds of unchastity and of unnatural crimes. - Lev 18:19 prohibits intercourse with a woman during her uncleanness. טמאה נדּת signifies the uncleanness of a woman's hemorrhage, whether menstruation or after childbirth, which is called in Lev 12:7; Lev 20:18, the fountain of bleeding. The guilty persons were both of them to be cut off from their nation according to Lev 20:18, i.e., to be punished with death.
Lev 18:20
"To a neighbour's wife thou shalt not give שׁכבתּך thy pouring as seed" (i.e., make her pregnant), "to defile thyself with her," viz., by the emissio seminis (Lev 15:16-17), a defilement which was to be punished as adultery by the stoning to death of both pa…
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