Thou shalt not uncover the nakedness of thy brother's wife: it is thy brother's nakedness.
a. We must remember that the nations of the Canannites did practice these offences.
1). Leviticus 18:24-27 Defile not ye yourselves in any of these things: for in all these the nations are defiled which I cast out before you:
25 And the land is defiled: therefore I do visit the iniquity thereof upon it, and the land itself vomiteth out her inhabitants.
26 Ye shall therefore keep my statutes and my judgments, and shall not commit any of these abominations; neither any of your own nation, nor any stranger that sojourneth among you:
27 (For all these abominations have the men of the land done, which were before you, and the land is defiled;)
1. “Thou shalt not uncover the nakedness of thy brother's wife…”
a. uncover [1540 * galah][Strong; a primitive root; to denude (especially in a disgraceful sense); by implication, to exile (captives being usually stripped); figuratively, to reveal:--+ advertise, appear, bewray, bring, (carry, lead, go) captive (into captivity), depart, disclose, discover, exile, be gone, open, X plainly, publish, remove, reveal, X shamelessly, shew, X surely, tell, uncover.] .][AMG Complete Word Study Dictionary Old Testament: A verb meaning to reveal, to uncover, to remove, go into exile, to expose, to disclose. It is used with the words ear (1 Samuel 9:15; 20:2, 12, 13) and eyes (Numbers 24:4), meaning to reveal. On occasion, it is used in the expression to uncover the nakedness of, which often implies sexual relations.]
b. nakedness [6172 * ‘ervah][Strong: nudity, literally (especially the pudenda) or figuratively (disgrace, blemish):--nakedness, shame, unclean(-ness).][AMG Complete Word Study Dictionary Old Testament: A feminine noun expressing nakedness. This word scan pertain to physical nakedness of a man or woman (Genesis9:22, 23; Exodus 20:26)…When used with the verb galah (1540), meaning to uncover or remove, and ra’ah (7200), meaning to see, one finds a common euphemism for sexual relations.]
c. Louis Goldberg, A Study Guide Commentary on Exodus: The law did make one exception to Leviticus 18:16, in the practice of levirate marriages, in which a widow was taken as a wife by the brother of the deceased when the deceased had left no son. This exception allowed family lines to be preserved and inheritances to remain unbroken.
1). Deuteronomy 25:5-10 If brethren dwell together, and one of them die, and have no child, the wife of the dead shall not marry without unto a stranger: her husband's brother shall go in unto her, and take her to him to wife, and perform the duty of an husband's brother unto her.
6 And it shall be, that the firstborn which she beareth shall succeed in the name of his brother which is dead, that his name be not put out of Israel.
7 And if the man like not to take his brother's wife, then let his brother's wife go up to the gate unto the elders, and say, My husband's brother refuseth to raise up unto his brother a name in Israel, he will not perform the duty of my husband's brother.
8 Then the elders of his city shall call him, and speak unto him: and if he stand to it, and say, I like not to take her;
9 Then shall his brother's wife come unto him in the presence of the elders, and loose his shoe from off his foot, and spit in his face, and shall answer and say, So shall it be done unto that man that will not build up his brother's house.
10 And his name shall be called in Israel, The house of him that hath his shoe loosed.
2). A positive example is found in Ruth 4:10. While a negative example is found in Genesis 38:1-10.
3). This commandment was also cited by the Sadducee enemies of Jesus trying to trap him.
a). Mark 12:18-27 Then come unto him the Sadducees, which say there is no resurrection; and they asked him, saying,
19 Master, Moses wrote unto us, If a man's brother die, and leave his wife behind him, and leave no children, that his brother should take his wife, and raise up seed unto his brother.
20 Now there were seven brethren: and the first took a wife, and dying left no seed.
21 And the second took her, and died, neither left he any seed: and the third likewise.
22 And the seven had her, and left no seed: last of all the woman died also.
23 In the resurrection therefore, when they shall rise, whose wife shall she be of them? for the seven had her to wife.
24 And Jesus answering said unto them, Do ye not therefore err, because ye know not the scriptures, neither the power of God?
25 For when they shall rise from the dead, they neither marry, nor are given in marriage; but are as the angels which are in heaven.
26 And as touching the dead, that they rise: have ye not read in the book of Moses, how in the bush God spake unto him, saying, I am the God of Abraham, and the God of Isaac, and the God of Jacob?
27 He is not the God of the dead, but the God of the living: ye therefore do greatly err.
2. “…it is thy brother's nakedness.”
a. Your brother’s wife’s nakedness is his nakedness. Sexual relations between brother-in-laws and sister-in-laws were forbidden