If a man lies with his father’s wife, he has uncovered his father’s nakedness; both of them shall surely be put to death; their blood is upon them.
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...
Sins against the seventh commandment are here ordered to be severely punished. These are sins which, of all others, fools are most apt to make a mock at; but God would teach those the heinousness of the guilt by the extremity of the punishment that would not otherwise be taught it. I. Lying with another man's wife was made a capital crime.
Commenting on Leviticus 20:10-21
And the man that lieth with his father's wife,.... Whether she be his mother, or another woman, as the Targum of Jonathan; that is, whether she is his own mother, or a stepmother, or whether he did this in the lifetime of his father, or after his death, or whether she was betrothed or married, it mattered not; according to the Jewish tradition (d), this...