Why Do We Read the Incest Prohibitions on Yom Kippur?

Not to Act Like Canaanites or Egyptians

The beginning of the Yom Kippur afternoon Torah reading (Leviticus 18:3) exhorts the Israelites to be different from the Egyptians and from the Canaanites and not to follow their “laws” but to follow God’s laws:

^{ויקרא יח:ג} כְּמַעֲשֵׂה אֶרֶץ מִצְרַיִם אֲשֶׁר יְשַׁבְתֶּם בָּהּ לֹא תַעֲשׂוּ וּכְמַעֲשֵׂה אֶרֶץ כְּנַעַן אֲשֶׁר אֲנִי מֵבִיא אֶתְכֶם שָׁמָּה לֹא תַעֲשׂוּ וּבְחֻקֹּתֵיהֶם לֹא תֵלֵכוּ: ^יח:ד אֶת מִשְׁפָּטַי תַּעֲשׂוּ וְאֶת חֻקֹּתַי תִּשְׁמְרוּ לָלֶכֶת בָּהֶם אֲנִי יְ-הוָה אֱלֹהֵיכֶם:

^{Lev 18:3} You shall not copy the practices of the land of Egypt where you dwelt, or of the land of Canaan to which I am taking you; nor shall you follow their laws. ^18:4 My rules alone shall you observe, and faithfully follow My laws: I YHWH am your God.

The rest of the reading explains what laws ostensibly differentiate the expected Israelite behavior from that of their Canaanite neighbors and their former Egyptian hosts:

• Various laws of incest (vv. 6-18).
• Four other sexual infractions (v. 19, 22-23).
• Molech worship (child sacrifice?, v. 21).

The chapter ends with further exhortations, explaining that the Canaanites’ failure to observe these laws caused them to be spewed out of the land:

^{ויקרא יח:כד} אַל תִּטַּמְּאוּ בְּכָל אֵלֶּה כִּי בְכָל אֵלֶּה נִטְמְאוּ הַגּוֹיִם אֲשֶׁר אֲנִי מְשַׁלֵּחַ מִפְּנֵיכֶם. ^יח:כה וַתִּטְמָא הָאָרֶץ וָאֶפְקֹד עֲו‍ֹנָהּ עָלֶיהָ וַתָּקִא הָאָרֶץ אֶת יֹשְׁבֶיהָ.

^{Lev 18:24} Do not defile yourselves in any of those ways, for it is by such that the nations that I am casting out before you defiled themselves. ^18:25 Thus the land became defiled; and I called it to account for its iniquity, and the land spewed out its inhabitants.

A Yom Kippur Reading

According to Rabbinic Jewish custom, this section is read during the minchah (afternoon) service on Yom Kippur. The practice is first mentioned in the Babylonian Talmud (Megillah 31a):

ביום הכפורים קורין אחרי מות ומפטירין כי כה אמר רם ונשא, ובמנחה קורין בעריות ומפטירין ביונה.

On Yom Kippur [morning] we read Acharei Mot (= Lev 16), and for the prophetic reading— “For thus said He who high aloft forever dwells” (= Isaiah 57:14-58:14). In the afternoon we read [the section about] incest (= Lev 18), and for the prophetic reading—the book of Jonah.

The other readings are intuitive. Leviticus 16 is an appropriate choice for the morning reading as it describes the Temple service on Yom Kippur. Isaiah 58 describes what a fast day that God approves of should look like, and the book of Jonah puts sharp focus on repentance. But the reason for reading the passage about incest is unclear; what is its connection to Yom Kippur? A variety of explanations have been offered over the centuries—often a sign that no single compelling answer exists.

Getting Sinners to Repent

In his Halachot (Yom Kippur), R. Isaac ibn Ghiyyat (1038-1089) writes:

ובמנחה מוציאין ספר תורה וקורין ג’ בעריות שמא יש אחד שנכשל (בעורה) [בעבירה] דערוה ושכח וכששומע נזכר וחוזר ומתודה עליה

During minchah, they take out a Torah scroll and three read from the incest laws, as perhaps there is someone [in the synagogue] who succumbed to a sexual sin but forgot, and when he hears the reading he will remember and repent for it.

Moses Maimonides (1138-1204) picks up on ibn Ghiyyat’s core idea but suggests that it is read in order to embarrass the sinners in the synagogue into repentance (Mishneh Torah, Laws of Prayer 13:11):

כדי שיזכור ויכלם כל מי שנכשל באחת מהן ויחזור בתשובה

So that whoever may have succumbed and sinned with one of these will remember, and be ashamed, and repent.^[1]

In a similar vein, in his Siddur (#214), Rashi (1040-1105) suggests that the reading is to scare people into repentance:

כדי שישמעו בה כריתות של עריות ויפרשו מהן

So that people hear the punishment of excision which comes to those who violate the sexual prohibitions, and then they will separate themselves from these sins.^[2]

R. Abraham ben Nathan Even HaYarchi (12^th cent.), in his Sefer HaManhig (Laws of Tzom Kippur, p. 354), describes a custom that went along with the reading:

והמנהג להודיע לרבי’ ולהזהיר על העריות, וכל מי שיש בו מאלה יקבל על עצמו לפרוש מהן ולהתוודות עליהן ויתכפר לו, כך קיבלתי מרבותיי בצרפת.

The custom is to announce a public warning about sexual sins, and anyone who has sinned with any of these should accept upon himself to separate from them and to confess them, and receive atonement for them. This I learned from my rabbis in France.

The difficulty with all of these interpretations, however, is that they do not explain why this sin and not any other sin gets such close attention on Yom Kippur.

Sexual Misconduct Is Endemic

In his Talmud commentary (ad loc.), Rashi explains why these specific sins were chosen:

שמי שיש עבירות בידו יפרוש מהן, לפי שהעריות עבירה מצויה, שנפשו של אדם מחמדתן ויצרו תוקפו

All who have been guilty should separate themselves from these sins. For sexual violations are widespread, since people are continually attracted to these [sins], and their impulses overcome them.^[3]

Rabbenu Asher ben Yehiel (Rosh, 1250-1327) offers a similar argument (Tosafot HaRosh, ad loc.):

משום שזהו דבר שנפשו של אדם מתאוה ונכשלים בהם כל ימות השנה וגם ביום הכפורים… ולכך קורין בעונשין דעריות כדי שישימו לב ויחזרו בתשובה.

[Forbidden sexuality] is something that people lust for and infractions take place every day of the year, even on Yom Kippur itself… That is why we read about the punishments for improper sexual conduct,^[4] so people take note and repent.

“Dangers” Lurking in Synagogue on Yom Kippur

A creative application of this view appears in a gloss of the Tosafot (12^th/13^th centuries) on the Talmud (Meg. ad loc.), who argue that we read about forbidden sexuality on Yom Kippur:

לפי שהנשים מקושטות בשביל כבוד היום לפיכך צריך להזכירם שלא יכשלו בהן

[S]ince [on Yom Kippur] the women are dressed in their finery in honor of the [holy] day, accordingly we have to remind them [= the men] not to sin with them [= the women].

Ensuring Correct Beliefs – Meiri

In his Book on Repentance (חיבור התשובה, Meishiv Nefesh 2:9), Rabbi Menahem ha-Meiri (1249-1310) takes a very different position, making no reference to the particulars of the sexual admonitions of the chapter. Instead, he writes that since Yom Kippur is meant as a day for human perfection, we must rid ourselves of improper beliefs on this day. This is the Torah’s meaning in telling us not to be like Egyptians and Canaanites, meaning, for him, that we should not have their worldview. In other words, this passage is chosen since it refers to the ways of the Egyptians and Canaanites, not because it highlights incest:

היום ההוא מוכן לכל שלמות, בהיותו משולל מכל ענין חמרי . . . מצורף אל מה שיחס לו בבואו בהקרבת כל אלו הקרבנות . . . שבהם הערה לכל בטול אמונה כוזבת כמו שאמר בפרוש, ולא יזבחו עוד [לשעירים] וגו’, וכן אמר כמעשה ארץ מצרים וגו’, כמו שידוע השתקעם שם באמונות כוזבות כמו שקדם

This day (Yom Kippur) is designed for every sort of perfection, since all material enjoyment is forbidden… add to this what is implied in the bringing of all these sacrifices… which point to the nullification of every false belief, as it says explicitly [Lev 17:7]: ‘That they may offer their sacrifices no more [to the goat-demons]…” And it says “the practices of the land of Egypt…” As is known, they [the Israelites in Egypt] were sunk there in false beliefs, as [the passage] states at the outset.

Meiri’s unusual idea that this passage is read because of the beliefs that it promotes fits with his understanding of the morning reading of the Yom Kippur sacrificial service. The morning’s Torah reading about the sacrifices and order of Temple service for Yom Kippur, including the scapegoat, serves, according to Meiri, to combat the belief in goat-demons (seirim) that many argue was rampant in biblical times.^[5] That is why the Torah writes just after the description of the Yom Kippur service:

^{ויקרא יז:ז} וְלֹא יִזְבְּחוּ עוֹד אֶת זִבְחֵיהֶם לַשְּׂעִירִם אֲשֶׁר הֵם זֹנִים אַחֲרֵיהֶם

^{Lev 17:7} That they may offer their sacrifices no more to the goat-demons (seirim) after whom they stray.^[6]

Divine Reward and Punishment

Furthermore, says Meiri, Lev 18 teaches us the principle of divine reward and punishment, since the Canaanites were punished harshly for their immorality:

והיא הסבה להיות כל קריאות היום הנכבד בזה הסדר בשחרית ובמנחה, בשחרית ספור עבודת היום, ובמנחה פרשת כמעשה ארץ מצרים, כל זה הערה לבטול אמונה כוזבת מצורף אל הסכמת אמונת גמול וענש כמו שמיעד בספור פרשת עריות.

This is the reason that the readings of this important day, morning and afternoon, all relate to this theme. The morning [reading] describes the priestly service of the day, and the afternoon reading [is about] “the practices of the land of Egypt.” This all points to the nullification of false belief; additionally [it promotes] the belief in reward and punishment, which is what is taught in the passage about sexual misconduct.

Meiri’s point is that the passage ends with the statement that the Canaanites, who violated these sexual prohibitions, were kicked out of the land, and if the Israelites wish to be rewarded with remaining on the land, they must follow these laws. That, in Meiri’s view, teaches the Israelites about reward and punishment. Thus, once they have removed false, idolatrous beliefs by reading the Yom Kippur sacrificial service, they are ready to learn about true beliefs from the Torah reading that highlights the dangers of the practices of Egypt and Canaan.

It’s a Metaphor – Midrash

An entirely different approach is taken in a lost midrash, quoted by a number of medieval scholars, who offer a metaphorical understanding of the Torah reading:

ובמדרש יש שלכך קורין בעריות לפי שישראל עושין רמז להקב”ה שכשם שהזהיר אותם שלא לגלות ערוה כך לא תגלה ערותם בעונותם.

An explanation in the midrash is that we read about forbidden sexuality to hint to God that just as He asked us not to “uncover nakedness,” so also God should not uncover the Israelites’ nakedness, [namely,] their sins.^[7]

The Importance of 24 – Rokeach

A similar suggestion was made by R. Elazar of Worms (1176-1278), a German pietist and mystic, in his Rokeah (Yom Kippur 216). He counts 24 references to forbidden sexuality in this chapter and sees the number as significant:

כי כ”ד עריות כתובי’ באחרי מות [וכ”ד כפרות כתובין בעניין יום הכפורים באחרי מות]^[8]ובאמור אל הכהנים [ובפנחס ובאתה תצוה ובמדבר סיני].

For 24 mentions of ervah (forbidden sexual acts) appear in Acharei Mot^[9] [and 24 “atonements” are written in the passages about Yom Kippur in Acharei Mot] and Parashat Emor [and in Pinchas, Tetzaveh, and Bemidmar Sinai].^[10]

ה’ מהם כפורים
וה’ לכפר
וט’ וכפר
וד’ יכפר
וא’ מכפר

5 kippurim (“atonement”),^[11]
5 lekhaper (“to atone”),^[12]
9 vekhipper (“and he will have atoned”),^[13]
4 yekhaper (“he will atone”),^[14]
1 mekhaper (“atoning”).^[15]

הרי כ”ד כפרות לכפר על כ”ד ערוה באחרי מות וכ”ד גילוין בעריות ולכפר על כל העובר כ”ד ספרים לכפר על כל כ”ד שעות ביום וכ”ד אכילות בבראשית מן ולכם יהיה לאכלה עד ואכל וחי לעולם

Altogether, these 24 atonements atone for the 24 references to forbidden sexuality in Acharei Mot, and for the 24 “revealings” that appear in the [passages] about sexual violations,^[16] and for the violation of the 24 books [of the Bible],^[17] and for [violations that occurred during any of] the 24 hours of the day, and for the 24 [times that] eating [is mentioned] in Genesis from (Gen 1:29) “they shall be yours for food” to (Gen 3:22), “lest they eat and live forever.”^[18]

R. Elazar notes the correspondence between the number of sexual sins and the number of times the word “atone” appears in select YK related sections, and sees this as evidence that Yom Kippur, the Day of Atonement, atones for all the sexual sins (and many other sins, based on his creative application of the number 24).^[19]

A Day of Matchmaking – Mishnah

The final mishnah of tractate Taanit (4:8) suggests that Yom Kippur once had a very different atmosphere:

אמר רבן שמעון בן גמליאל לא היו ימים טובים לישראל כחמשה עשר באב וכיום הכפורים שבהן בנות ירושלם… יוצאות וחולות בכרמים ומה היו אומרות בחור שא נא עיניך וראה מה אתה בורר לך אל תתן עיניך בנוי תן עיניך במשפחה (משלי ל”א) שקר החן והבל היופי אשה יראת ה’ היא תתהלל

Rabban Simeon ben Gamaliel said: Never were there any more joyous festivals in Israel than the Fifteenth of Av and Yom Kippur, for on them the maidens of Jerusalem used to go… and dance in the vineyards, saying: Young man, look and note well how you choose. Regard not beauty alone, but rather look to [the woman’s] family, for “Grace is deceptive, beauty is illusory; it is for her fear of the Lord that a woman is to be praised” (Proverbs 31:30).^[20]

In an article in Beit Talmud, written in 1882, Yaakov Toprower of Leipzig suggested that if Yom Kippur was once a day of matchmaking, it made sense to read publically a section of the Torah that reminded people whom they could and, more to the point, could not marry.^[21]

Following the Order of the Torah

A much more prosaic explanation was first suggested by the great scholar of liturgy, Rabbi Ismar Elbogen (1874-1943), and was subsequently adopted by a number of modern Jewish scholars, including Ezra Fleischer, Moshe David Herr, and Joseph Tabory.^[22] Elbogen notes that in the morning, we read from Leviticus 16. Although the standard custom now is to stop at the end of the chapter, a number of medieval halakhists record the custom of reading both chs. 16 and 17 in the morning.

Two anonymous halakhic sources, the 13^th cent. Tanya Rabbati (Laws of Yom Kippur, 81) and the 14^th cent. Kol-Bo (20), describe this as the set custom:

Tanya Rabbati

וקורין בפרשת אחרי מות עד כמעשה ארץ מצרים.

And they read from Parashat Acharei Mot until “like the practices of the land of Egypt” (ch. 18).

Sefer Kol-Bo

באחד קורין ו' בסדר אחרי מות כל ענין יום הכפורים עד כמעשה ארץ מצרים

From the first [Torah], six men read the portion of Acharei Mot until “like the practices of the land of Egypt (ch. 18).

Similarly, R. Zedekiah ben Abraham Anaw (c. 1210-1280), in his Shibbolei HaLeket (Yom Kippur, 320) describes the proper place to stop as a matter of debate, while R. Isaac of Vienna (ca. 1200-1270), in his Or Zarua (Laws of Holiday Readings, 393), makes the proper ending depend on whether Yom Kippur falls out on a Shabbat or a week day:

Shibolei HaLeket

וקורין פרשת אחרי מות עד כמעשה ארץ מצרים ויש (שמדלגין) [שרגילין] לקרות פסקא ראשונה לבד מתחילת הפרשה עד ויעש כאשר צוה ה’ את משה לפי שזה הוא סדר עניינו של יום ולא יותר

They read Parashat Acharei Mot until “like the practices of the land of Egypt” (ch. 18). And there are those who read only the first section, from the beginning of the parashah until “and Moses did what God commanded” [in other words, all of ch.16, as is the current practice] and no more, since this covers the material relevant to the day.

Or Zarua

ביוה”כ קרו ו’ גברי מן אחרי מות עד ויעש כאשר צוה ה’ את משה וכד מיקלע בשבתא קרו ז’ גברי מן אחרי מות עד כמעשה ארץ מצרים

On Yom Kippur, six men read from Acharei Mot until “and Moses did what God commanded” (the end of ch. 16). But when it falls out on Shabbat, seven men read from Acharei Mot until “like the practices of the land of Egypt” (ch. 18).

Another German scholar and rabbi from the same period as Elbogen, Adolf Büchler (1867-1939), drew a comparison with the Rosh Hashanah readings that are contiguous.^[23] The primary reading on Rosh Hashanah is Genesis 21 (Isaac’s birth), with the second day reading from Gen 22 (the Akedah, binding of Isaac) picking up where the reading left off, though in this case, the connection between the Akedah and Rosh Hashanah is adduced in rabbinic literature.

According to this approach the connection between the incest laws and Yom Kippur is practical—it is the passage that immediately follows the morning reading. Nevertheless, this suggestion is not definitive, since we do not know how far back the custom of reading both chapters 16 and 17 in the morning goes, as the Talmud never indicates where the reading is to end.

A New Explanation

In my “Why the Torah Prohibits Incest,” (TheTorah, 2017), I note that R. Nissim of Marseilles (14^th cent.) and Shadal (1800-1865) both suggested a sociopolitical reason for these laws, namely, to force people to look beyond their own nuclear families for marriage, and to connect with other families, and thereby bring unity to humanity. (See my essay for details.) Following this rationale, perhaps reading these laws delivers an appropriate message for the end of Yom Kippur.

The idea fits well with the afternoon haftarah, in which God sends the Israelite prophet Jonah to preach repentance to the Assyrian people of Nineveh. It also fits well with the haftarah reading on Yom Kippur morning, which, while exhorting us (Isaiah 58:7) to remember our own kin (ומבשרך לא תתעלם), demands that we pursue justice and take care of those beyond our narrow family confines:

^{ישעיהו נח:ו} הֲלוֹא זֶה צוֹם אֶבְחָרֵהוּ פַּתֵּחַ חַרְצֻבּוֹת רֶשַׁע הַתֵּר אֲגֻדּוֹת מוֹטָה וְשַׁלַּח רְצוּצִים חָפְשִׁים וְכָל מוֹטָה תְּנַתֵּקוּ: ^נח:ז הֲלוֹא פָרֹס לָרָעֵב לַחְמֶךָ וַעֲנִיִּים מְרוּדִים תָּבִיא בָיִת כִּי תִרְאֶה עָרֹם וְכִסִּיתוֹ וּמִבְּשָׂרְךָ לֹא תִתְעַלָּם:

^{Isa 58:6} This is the fast I desire: to unlock fetters of wickedness, and untie the cords of the yoke, to let the oppressed go free; to break off every yoke. ^58:7 It is to share your bread with the hungry, and to take the wretched poor into your home; when you see the naked, to clothe him, and not to ignore your own kin.