The nakedness of thy father's wife shalt thou not uncover: it is thy father's nakedness.

Thou shalt not uncover the nakedness of thy father's wife: for it is the nakedness of thy father.

The nakedness of the wife of thy father thou dost not uncover; it is the nakedness of thy father.

And you may not have sex relations with your father's wife: she is your father's.

You shall not expose the nakedness of your father's wife; for it is the nakedness of your father.

Turpitudinem uxoris patris tui non revelabis: turpitudo patris tui est.

Compare the case of Reuben, Genesis 49:3-4. See 1-Corinthians 5:1.

The nakedness of thy father's (d) wife shalt thou not uncover: it [is] thy father's nakedness.
(d) Which is your stepmother.

The nakedness of thy father's wife shalt thou not uncover,.... That is, who is indeed a man's father's wife, but not his own mother, but a stepmother or mother-in-law; or otherwise this law would coincide with the former; a man lying with such an one is accursed by the law, Deuteronomy 27:23; such an incestuous copulation was that of Reuben with Bilhah, and Absalom with his father's concubines or secondary wives, and such an incestuous marriage was that of the Corinthians, 1-Corinthians 5:1; and of Antiochus Soter, king of Syria, with Stratonice his mother-in-law (c): and even it was criminal to do this after a father's death, as Jarchi interprets it; and though she was only betrothed, and not married, and the father dead after such betrothing; as Gersom; nay, though she was divorced by the father, yet was not lawful for the son to have, no, not after his death:
it is thy father's nakedness; being espoused to him, and so one flesh with him; and the son and father being one flesh, such a mixture must be unlawful; and since then the nakedness of a mother-in-law is the father's, then surely that of an own mother's must be so likewise, which confirms a sense given of it in Leviticus 18:7, Cicero (d) exclaims against such marriages as incredible and unheard of, as instances of unbridled lust and singular impudence.
(c) Vid. Julian. in Misopogon, p. 72, &c. (d) Orat. 14. pro A. Cluentio Avito.

Intercourse with a father's wife, i.e., with a step-mother, is forbidden as uncovering the father's nakedness; since a father's wife stood in blood-relationship only to the son whose mother she was. But for the father's sake her nakedness was to be inaccessible to the son, and uncovering it was to be punished with death as incest (Leviticus 20:11; Deuteronomy 27:20). By the "father's wife" we are probably to understand not merely his full lawful wife, but his concubine also, since the father's bed was defiled in the latter case no less than in the former (Genesis 49:4), and an accursed crime was committed, the punishment of which was death. At all events, it cannot be inferred from Leviticus 19:20-22 and Exodus 21:9, as Knobel supposes, that a milder punishment was inflicted in this case.