ESSAY
Law and History: How to Read the Law of Moses (Part 2)

The second in a series of studies in Deuteronomy.


Deuteronomy 22:30: A man shall not take his father’s wife, and shall not uncover his father’s wing (Hebrew: kanaf).

There are a number of unusual features in this law that mark it out from the previous context, indicating that it is introductory to the following paragraph about the assembly of Yahweh, even though this verse does not speak of the “assembly” directly. To begin with, this law is apodictic in contrast with the case laws in the preceding verses (22:13-29), but similar to the initial laws on the Seventh Word in 22:9-12. Also, in contrast with the laws from 22:13-19, but similar to the laws in 23:2-8, this law contains an evident historical allusion. Finally, 22:30 is linked to the laws in Leviticus 18 about forbidden marriages and to the law in Numbers 15:37-39 about Israelite clothing. It is the clothing laws that indicate this verse is already focused on the idea of Israel’s special place as Yahweh’s treasured nation. Also, the reference to clothing probably alludes to a second story in Genesis, besides the primary and obvious allusion.

I am suggesting that what may appear on the surface to be a simple command is rich with historical allusions, links with other laws, and layers of presupposed background. It may be helpful here to list these before turning to the exposition.

  1. The story of Reuben violating Bilhah, though not directly alluded to, nevertheless clearly stands out.
  2. The similar laws in Leviticus 18:8 and 20:11 supply another layer of legal background.
  3. The law in Numbers 15:37-41, alluded to even more directly in Deuteronomy 22:12, is alluded to here in the use of the Hebrew word for “wing.” Significantly, in Numbers this law provides the immediate backdrop for the story of the rebellion led by Korah and the Reubenites, which reinforces point 5 below.
  4. The reference to uncovering the wing of the robe suggests an allusion to another famous story in Genesis, the sin of Ham.
  5. The motivation for this law in the story of the Reubenite leaders’ rebellion in Numbers 16 becomes clearer as we read onward in Deuteronomy and discover this law’s emphatic repetition in Deuteronomy 27:20 together with the curse on Reuben in 33:6.

I need to address one more question before entering into detailed exposition. That is:  would these allusions have been obvious to a reader of the law in Moses’ day? They did not have tools for Biblical research that we have. Would they remember the laws and stories so readily? Actually, I believe it would have been easier for an ancient reader to note the various layers in the law, in part because we are not accustomed to reading the law with allusions in mind, but also because in Moses’ day, the whole of the Scripture was just the books that Moses wrote. The stories in Genesis of Israel’s great ancestors would have been told over and over.  Each tribe would know as much as possible about its own father, though it was sometimes embarrassing.

Deuteronomy is such a long book that as we read it, we may forget where it begins:  “These are the words that Moses spoke to all Israel . . . in the fortieth year, on the first day of the eleventh month” (Deuteronomy 1:1, 3). Deuteronomy is Moses’ farewell sermon just before his death, his parting words to the people he loved. We can be sure that they are listening attentively. We should also imagine what happens in the congregation of listeners, when Moses comes to the law in Deuteronomy 22:30, with the story of Reuben obviously being alluded to. I can see the other tribes of Israel glancing toward the Reubenites, and the Reubenites holding down their heads in shame. Everything here is highly personal. Remembering and noticing the most obvious allusions and background would hardly require effort for them, though it does for us. Of course, picking up the entire multi-layered complex of references would no doubt have required multiple readings and meditation, but that is exactly what God commanded Joshua to do (Josh. 1:8).

Reuben and Bilhah

Thus, it is not too much to suggest a historical allusion here to the story of Reuben, who lay his father’s wife, Bilhah (Gen. 35:22). The incident with Reuben is the only recorded case of a man lying with his father’s wife. Moreover, through Jacob’s curse on his firstborn son (Gen. 49:3), Reuben’s sin receives special emphasis in Genesis. This episode, though recorded briefly and without emotional language, is so prominent in the story of Israel that even though the law here is probably prohibiting marriage to a father’s former wife rather than simple incest, the allusion still stands. Israel’s history was short enough and the incident was famous enough that it would be impossible for an Israelite of Moses’ day not to recall Reuben’s sin when reading this law.

We may wonder why Reuben would commit such a sin. I believe Gordon Wenham is correct in seeing Reuben’s sin as a political act, not a sensual one.[i] The context of the story is important. In the paragraph immediately preceding the record of the incident, Rachel had just died giving birth to Benjamin (Gen. 35:16-21). This put an end to the long-standing rivalry between Leah and Rachel, which had centered on having children (Gen. 29:31-30:24), finally allowing Leah to have the limelight she so desperately sought. There remained, however, one potential source of competition, Bilhah. Since she had been Rachel’s slave, her children would be seen as belonging to Rachel. Reuben, who seems to be especially close to his mother (Gen. 30:14), would realize, as Wenham points out, that by lying with Bilhah, he could cut Jacob off from Rachael’s slave, ensuring his mother’s preeminence.[ii]

Legal Background in Leviticus

The laws in Leviticus provide another aspect of what is presupposed in this text. The entire section of Deuteronomy 22:9-23:14 is about the Seventh Word, which is also the central concern of the laws in Leviticus 18. Though the allusion to Reuben remains central, it is not all that the law is about. The expression “take his father’s wife” in the immediate context seems clearly to mean “marry his father’s wife,” for just a few verses before this the expression “take a wife” is used clearly to mean “marry” (Deuteronomy 22:13–14; cf. also 7:3; 20:7; 21:11; 24:1, 3–5; 25:5, 7-8). It is doubtful that this law concerns a son seeking to marry his own mother. Rather it addresses the case of a man seeking to marry a former concubine or a former wife of the father, other than his own mother.

However, the use of the word “uncover” in Deuteronomy 22:30 clearly links this law with the sexual prohibitions of the book of Leviticus (Lev 18:6–19; 20:11, 17–21), for although the word “uncover” is not a technical term referring only to sexual sins, that usage is prominent in Leviticus where the Hebrew word for “uncover” occurs 24 times in 20 verses exclusively speaking of sexual sin, not only unlawful marriage.[iii] Thus, the verse would be prohibiting a son from marrying his father’s wife after the father had died or divorced his wife, but also forbidding a son from sexual relationships with a concubine while the father lived.[iv]

For modern people these laws in Leviticus and Deuteronomy might seem superfluous, but in ancient Israel where polygamy was tolerated, the law was important and necessary. An older man might take a concubine who was as young as, or even younger, than his son. For example, David’s concubine, Abishag, was certainly closer to the age of Adonijah than David.  Since she was renowned for her beauty, it was natural perhaps for Adonijah to desire her, though Solomon was no doubt correct when he suspected political motives for Adonijah’s request (1Kings 2:13-25). At any rate, it is marriages of this sort that the law forbids, though, as we have seen, it would include the prohibition of the specific sort of adultery that Reuben committed in lying with Bilhah and that Absolom committed by lying with David’s concubines.

It is also noteworthy that the laws in Leviticus 18 are both prefaced and followed by warnings for the Israelites not to be like the inhabitants of Canaan, because the land vomited its former inhabitants because of their sexual immorality (18:1-5, 24-30). The law of Leviticus 20:11, which in context specifically addresses adultery rather than marriage with a concubine after a father has died (cf. 20:10), provides important background as well, since it pronounces the death penalty on the man who lies with his father’s wife. Thus, Leviticus tells us that individuals who imitate Reuben’s sin and societies that imitate the Canaanites’ sin deserve the death penalty. Certainly members of the tribe of Reuben would have noticed that feature of Leviticus and remembered it well.  They would not be alone, of course, in recalling such laws when they heard Moses’ words in Deuteronomy.

The Father’s Wing

The law in Deuteronomy 22:30 also contains an evident allusion to a law in the book of Numbers, though it is not obvious to a modern reader because of our translations. Deuteronomy here uses an odd term for the father’s garment by referring to the place where the tassels are attached as the “wings” or corners of the robe (cf. Numbers 15:38; Deuteronomy 22:12; 27:20). In other words, Deuteronomy 22:30 alludes to Numbers 15:38 by imitating its obviously symbolic language. The word kanaf originally refers to a bird’s wing (cf. Genesis 1:21; 7:14; etc.) but it is used in a few places to refer to the corners of a man’s garment.[v] Significantly in Deuteronomy 22:12, near the beginning of the section in Deuteronomy on the Seventh Word, there is a prior allusion to the original law in Numbers 15.  This makes for a double allusion to the law in Numbers in the larger context. Clearly Moses is drawing our attention to something.

What is the point of the allusion? We need to consider the law in Numbers to discover what Moses had in mind.  Numbers 15:37-39 teaches us that there is a theological meaning and purpose to its clothing requirement: “And Yahweh spake unto Moses, saying, Speak unto the children of Israel, and bid them that they make them tassels in the wings of their garments throughout their generations, and that they put upon the tassel of each wing a cord of blue: and it shall be unto you for a tassel, that ye may look upon it, and remember all the commandments of Yahweh, and do them; and that ye follow not after your own heart and your own eyes, after which ye use to play the harlot; that ye may remember and do all my commandments, and be holy unto your God. I am Yahweh your God, who brought you out of the land of Egypt, to be your God: I am Yahweh your God (Numbers 15:37-39).

The tassels with the blue cords essentially functioned as a “covenant memorial.” What does that mean? In Genesis 9:12-17, God told Noah that He would set the rainbow in the sky as a sign to remind God of His covenant promises to Noah. When God views the covenant sign, He remembers the covenant. So, too, the blue tassels on the wings of the garments were to remind Israelites of their holy calling to be the special people of Yahweh. The covenant is implied both in the expression “do all my commandments” and in the warning not to play the harlot. Also, the command to be holy expressed the core of Israel’s covenant obligation as the chosen race, for it was in order that they might be a holy people that Yahweh had delivered them from Egypt and brought them to Himself (Exodus 19:3-6).

The covenantal significance of the tassels on the “wings” of the garment suggests that the word “wing” has a symbolic meaning, especially since the tassels are specifically commanded to be blue — one of the most prominent colors of the tabernacle and the garments of the high priest. By putting blue on their garments to remind them of the covenant, the Israelites would also be associating themselves with the tabernacle and the priesthood, which again expresses their covenantal obligation to be a holy people.[vi] With such associations, I think it is legitimate to go one step further and speculate that the word “wing” is used to create an link with the cherubim in the tabernacle.

Perhaps it will help us to see the picture if we remember that the tabernacle was a multivalent symbolic model. Included among its meanings was that of being a model of Mt. Sinai. In other words, the tabernacle was a horizontal and mobile version of the great mountain of the Torah. Just as Sinai was divided into three areas — the border around the bottom of the mountain defined the forbidden area; a place half-way up the mountain where the elders sat before God was the area to which specially appointed men could come; the top of the mountain where God revealed Himself to Moses was the most exclusive area — the tabernacle also was divided into three areas, the courtyard, the Holy Place, and the Most Holy Place. Again, just as Moses received the tablets of the Ten Words at the top of the mountain, he placed them in the ark of the covenant in the Most Holy Place. Other associations also show that the tabernacle was a horizontal model of Mt. Sinai.

Mt. Sinai itself points elsewhere — eliciting Eden, the garden on the mountain top where God placed Adam and revealed Himself to him. To borrow an image from a time later than Eden, in the original creation there was a mountain that reached unto heaven. Babel was its counterfeit. Sinful mankind, led by Nimrod, attempted to make their own tower to heaven, their own garden sanctuary. God destroyed Nimrod’s tower, but in the days of Moses gave Israel a true mountain to heaven, a partially restored Garden of Eden. In that sense, the tabernacle fulfills the vision Jacob saw of a ladder to heaven with the angels of God ascending and descending on it (Gen. 28:12-15).

The winged cherubim of the Garden of Eden were replaced by the winged cherubim in the Most Holy Place, situated on the ark of the covenant where they symbolically guarded the covenant. The picture we have is that of cherubim who are always looking on the covenant with their wings extended. When the Israelites are told that the blue tassels on their wings are to remind them of the commandments and their obligation to be holy, it would have been natural to make the association with the blue tabernacle and its cherubim looking on the tablets of the Ten Words of the covenant.

It is also significant that the “wings” of the garment are first referred to in a passage that warns about idolatry as “playing the harlot” (Numbers 15:39) — the sin Israel committed with the Moabites in Numbers 25, which we are reminded of obliquely in Deuteronomy 23:3-6.  Worshiping other gods was the most basic and total rejection of the covenant with Yahweh, so living daily with the blue tassels visible to all was to remind the Israelites to be faithful as Yahweh’s priestly people. In this way, the use of “wings” in 22:30 alluding to the covenant memorial ties in with the emphasis on the “assembly of Yahweh” in 23:1-8 and serves, I believe, as an introduction to it.


Ralph A. Smith is pastor of Mitaka Evangelical Church, Tokyo, Japan.



[i] Gordon Wenham, Genesis 16-50 (Word Biblical Commentary; 2 vols.; Dallas:  Word Books, 1994) 2.325-26.

[ii] There is a slight possibility that Reuben may also be asserting his own rights of inheritance as firstborn, in a manner similar to Absolom’s attempt to steal David’s place by openly lying with his concubines.

[iii] The Hebrew word for “uncover” occurs in the entire Pentateuch 33 times in 29 verses, making its usage in Leviticus definitive in a similar context. The following list includes every instance in the Pentateuch:  Genesis 9:21; 35:7; Exodus 20:26; Leviticus 18:6–19; 20:11, 17–21; Numbers 22:31; 24:4, 16; Deuteronomy 22:30; 27:20; 29:29.  The verb is, thus, strongly associated with sexual sin, not just with unlawful marriage.

[iv] That a sin like Reuben’s is implied is also suggested by the parallel verse in Deuteronomy 27:20, the only other verse in the Old Testament to use the Hebrew expression “uncover the wing”:  ‘Cursed is he who lies with his father’s wife, because he has uncovered his father’s skirt [wing].’  And all the people shall say, ‘Amen.’” Here it is not marriage that is forbidden but “lying with” the father’s wife.

[v] Here is a list of every use of the Hebrew word kanaf in the Pentateuch:  Genesis 1:21; 7:14; Exodus 19:4; 25:20; 37:9; Leviticus 1:17; Numbers 15:38; Deuteronomy 4:17; 22:12, 30; 27:20; 32:11. There is some disagreement about where the tassels were to be hung. It might have been on the hem of the robe, as in some ancient pictures, or it might have been that Israelites wore an outer garment over their shoulders somewhat like a cape to which the tassels were attached.  Tigay comments: “Ancient Near Eastern art shows people wearing closed skirts and robes, not rectangular poncho-like garments. The four corners (lit., ‘wings’ or ‘extremities’) were probably either the points on scalloped hems or the places at which vertical bands of embroidery met the hems. Both styles, sometimes with tassels attached, are visible in ancient Near Eastern murals.”  Jeffrey H. Tigay, Deuteronomy (JPS Torah Commentary; Philadelphia: The Jewish Publication Society, 1996) 204.

[vi] In addition to the fact that the cords had to be blue, it was probably also the case that they were made of wool in order to be dyed. Tigay writes: “Numbers 15:38 requires that a blue cord be attached to each fringe.  According to early rabbinic sources, the blue cord is made of wool while the other cords are linen. In other words, the tassels are made of sha’atnez, the combination of fabrics forbidden in verse 11 [of Deuteronomy 22].  This interpretation most likely stems from biblical times, since it is highly unlikely that the rabbis would have initiated a practice contradicting a biblical prohibition. It is, in other words, an exception to the general rule stated in verse 11. According to Jacob Milgrom, the purpose of this exception is suggested by the fact that sha’atnez characterized the priestly garments; hence, wearing these tassels reminds every Israelite of the duty to strive for holiness like the priests, to become “a kingdom of priests and a holy nation” (Exod. 19:6)” ( Ibid.). Assuming the correctness of the early rabbinic sources, here is a case in which there is a blatant “contradiction” in the law intentionally made for the purpose of theological instruction.

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