Leviticus 18:21

And thou shalt not let any of thy seed. — Literally, And thou shalt not give any of thy seed. Those who violate the sanctity of the marriage ties will readily sacrifice their children. Hence the prohibition to offer up their children to idols follows the law about unchastity.

Pass through the fire to Molech. — Literally, to let it pass to Molech, that is, to put the child into the hands of the figure of Molech, when it fell into the fire which was kindled in the hollow statue of this idol. Molech, also called Milcom, which denotes king, is described as the hideous idol, or “the abomination of the Ammonites” (1 Kings 11:5; 1 Kings 11:11). The following graphic description has been handed down traditionally of this idol and its worship : — “Our sages of blessed memory say that whilst all other idols had temples in Jerusalem, Molech had his temple outside Jerusalem, in a place by itself. It was a brass and hollow image, bull-headed, with arms stretched out like a human being who opens his hands to receive something from his neighbour. Its temple had seven compartments, into which the offerers went according to their respective gifts. If one offered a fowl, he went into the first compartment; if a sheep, into the second; if a lamb, into the third; if a ram, into the fourth; if a bullock, into the fifth; if an ox, into the sixth; and if he offered his son, he was conducted into the seventh compartment. He first kissed the image, as it is written, ‘let the sacrificers of men kiss the calf’ (Hosea 13:2), whereupon a fire was kindled in Molech till its arms became red hot; the child was then put into its hands, and drums were beaten to produce tremendous noises so as to prevent the shrieks of the child reaching the father’s ears, lest he should be moved with pity towards his offspring.” It was to this idol that Solomon erected a temple on the southern side of Mount Olivet (2 Kings 23:13). This idolatrous worship was punished with death by stoning. (See Leviticus 20:2.)

Neither shalt thou profane. — Better, And thou shalt not profane, that is, by causing other nations to say that the Israelites regard their God as an inferior deity, and hence offer unto him animals, whilst to Molech they sacrifice their own children. Hence any act which is done in violation of his commands, or misrepresents God, or by which He is put on a par with other gods, is called “profaning the name of God.” (See Leviticus 19:12; Leviticus 20:3; Leviticus 21:6; Leviticus 22:2; Leviticus 22:32, &c.)