Nothing new occurs here, for the object of Moses was, by the enactment of penalties, to sanction the instruction lately given. By previously condemning incestuous marriages, he would cite the Israelites before God, in order that their consciences might abhor the crime, although he gave them nothing to fear from earthly judges; whereas now he alarms them by the dread of punishment, in case any should indulge themselves with too great security. He does not chastise the incestuous with rods, as if they were only guilty of a light offense; but he pronounces it to be a capital crime, if any had sinned against the law of nature; and first he condemns the step-mother and step-son to death, if they should have had connection with each other; he then makes the same decree with reference to the father-in-law and daughter-in-law; and, thirdly, the step-father and step-daughter. But when, if a man cohabits at the same time with a mother and her daughter, he extends the punishment to the mother also, it must be understood, provided she also consents to the abominable medley; for, if a man, against the mother’s will, seduces her daughter, and the mother is unable to resist it if she would, she is free from guilt. The same punishment is awarded to brother and sister, and nephew and aunt, and it is extended also to affinity; if any should cohabit with the wife of his uncle or his brother. We have elsewhere explained the meaning of the expression, “their blood shall be upon them;” i. e. , that the cause of their death is to be imputed to none but the gross criminals themselves, lest their judges, under the cloak of humanity, should shrink from being severe, since it often happens that those who do not sufficiently weigh the atrocity of the evil, are led away by an empty show of clemency. (95) Moreover, Moses indirectly hints that if the guilty be pardoned, vengeance will be thus provoked against the whole people, since iniquity is fostered by impunity, until it bursts out like a deluge. The penalty of childlessness corresponds with the crime, for it is just that those should be exterminated in barrenness from the world, who have endeavored to corrupt the holy race of Abraham with their adulterous seed.
(95) “Sont ployables, et faciles a pardoner;” are pliable and easily disposed to pardon. — Fr.