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. The adulterer and the adulteress that had joined in the sin must fall alike under the sentence: they shall both be put to death, Lev 20:10. Long before this, even in Job's time, this was reputed a heinous crime and an iniquity to be punished by the judges, Job 31:11. It is a presumptuous contempt of an ordinance of God, and a violation of his covenant, Pro 2:17. It is an irreparable wrong to the injured husband, and debauches the mind and conscience of both the offenders as much as any thing. It is a sin which headstrong and unbridled lusts hurry men violently to, and therefore it needs such a powerful restraint as this. It is a sin which defiles a land and brings down God's judgments upon it, which disquiets families, and tends to the ruin of all virtue and religion, and therefore is fit to be animadverted upon by the conservators of the public peace: but see Joh 8:3-11.

II.Incestuous connections, whether by marriage or not. 1. Some of them were to be punished with death, as a man's lying with his father's wife, Lev 20:11. Reuben would have been put to death for his crime (Gen 35:22) if this law had been then made. It was the sin of the incestuous Corinthian, for which he was to be delivered unto Satan, Co1 5:1, Co1 5:5. A man's debauching his daughter-in-law, or his mother-in-law, or his sister, was likewise to be punished with death, Lev 20:12, Lev 20:14, Lev 20:17. 2. Others of them God would punish with the curse of barrenness, as a man's defiling his aunt, or his brother's wife (Lev 20:19-21): They shall die childless. Those that keep not within the divine rules of marriage forfeit the blessings of marriage: They shall commit whoredom, and shall not increase, Hos 4:10. Nay it is said, They shall bear their iniquity, that is, though they be not immediately cut off by the hand either of God or man for this sin, yet the guilt of it shall lie upon them, to be reckoned for another day, and not be purged with sacrifice or offering.

III.The unnatural lusts of sodomy and bestiality (sins not to be mentioned without horror) were to be punished with death, as they are at this day by our law, Lev 20:13, Lev 20:15, Lev 20:16. Even the beast that was thus abused was to be killed with the sinner, who was thereby openly put to the greater shame: and the villany was thus represented as in the highest degree execrable and abominable, all occasions of the remembrance or mention of it being to be taken away. Even the unseasonable use of the marriage, if presumptuous, and in contempt of the law, would expose the offenders to the just judgment of God: they shall be cut off, Lev 20:18. For this is the will of God, that every man should possess his vessel (and the wife is called the weaker vessel) in sanctification and honour, as becomes saints.

They shall be burnt with fire - As there are worse crimes mentioned here, (see Lev 20:11 and Lev 20:17), where the delinquent is ordered simply to be put to death, or to be cut off, it is very likely that the crime mentioned in this verse was not punished by burning alive, but by some kind of branding, by which they were ever after rendered infamous. I need not add that the original, באש ישרפו baesh yishrephu, may, without violence to its grammatical meaning, be understood as above, though in other places it is certainly used to signify a consuming by fire. But the case in question requires some explanation; it is this: a man marries a wife, and afterward takes his mother-in-law or wife's mother to wife also: now for this offense the text says all three shall be burnt with fire, and this is understood as signifying that they shall be burnt alive. Now the first wife, we may safely presume, was completely innocent, and was legally married: for a man may take to wife the daughter if single, or the mother if a widow, and in neither of these cases can any blame attach to the man or the party he marries; the crime therefore lies in taking both. Either, therefore, they were all branded as infamous persons, and this certainly was severe enough in the case of the first wife; or the man and the woman taken last were burnt: but the text says, both he and they; therefore, we should seek for another interpretation of they shall be burnt with fire, than that which is commonly given. Branding with a hot iron would certainly accomplish every desirable end both for punishment and prevention of the crime; and because the Mosaic laws are so generally distinguished by humanity, it seems to be necessary to limit the meaning of the words as above.

If a man lie with a beast,.... A sin quite unnatural, exceeding shocking and detestable, forbid Lev 18:23,

he shall surely be put to death: by stoning, as the Targum of Jonathan adds; and this is the death such are condemned to in the Misnah (h):

and ye shall slay the beast; with clubs, as says the Targum of Jonathan; the reasons given in the Misnah (i), why the beast was to be slain, are, because ruin came to the man by means of it, and that it might not be said, as it passed along the streets, that is the beast for which such an one was stoned. Aben Ezra says it was to be slain, that it might not cause others to sin; and he adds, there are that say it was to cover the reproach: no doubt the true reason was to deter the more from this detestable sin, that if a beast, which was only accessory to it, and an instrument of it, was put to death, of how much sorer punishment must the man that committed it be worthy of, even of eternal wrath and destruction, and, unless repented of and forgiven, must be expected by him?

(h) Misn. Sanhedrin, c. 7. sect. 4. (i) Ibid.

Sanctify yourselves therefore, and be ye holy--The minute specification of the incestuous and unnatural crimes here enumerated shows their sad prevalence amongst the idolatrous nations around, and the extreme proneness of the Israelites to follow the customs of their neighbors. It is to be understood, that, whenever mention is made that the offender was "to be put to death" without describing the mode, stoning is meant. The only instance of another form of capital punishment occurs in Lev 20:14, that of being burnt with fire; and yet it is probable that even here death was first inflicted by stoning, and the body of the criminal afterwards consumed by fire (Jos 7:15).