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Yitzhaq Feder





Tum’ah: Ritual Impurity or Fear of Contagious Disease?



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Yitzhaq Feder





Tum’ah: Ritual Impurity or Fear of Contagious Disease?






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Tum’ah: Ritual Impurity or Fear of Contagious Disease?

Already in the early 2nd millennium B.C.E., people knew that diseases were contagious, and fear of contagion plays a key role in the Torah’s laws regarding the skin ailment, tzaraʿat. What does this mean for understanding other kinds of tum’ah?


Tum’ah: Ritual Impurity or Fear of Contagious Disease?

People scrambling to get away from a leper, in their haste the crowd has left an infant on the roadside, the leper strolls by, ringing a bell; representing attitudes to leprosy. R. Cooper.  (1885-1957) CC BY 4.0 Credit: Wellcome Collection

Early Evidence of Belief in Contagion

The emergence of germ theory in the 19th century was a paradigm shift for understanding the causes of disease and infection. Before this turning point, however, many cultures were aware that diseases can be contagious and came up with ways to avoid it.

The earliest unambiguous evidence that people were aware of contagion can be found in Old Babylonian letters from the Syrian city of Mari from the early 18th cent. B.C.E., which document illnesses and epidemics that assailed the kingdom during this period.[1]

For example, in a letter from Queen Šibtum to Zimri-Lim, the last king of Mari, it is related that her infected servant was placed in an isolated dwelling where she would eat her meals separately from the rest of the palace servants: “[No o]ne will approach her bed or chair.”[2] In a letter from King Zimri-Lim back to Queen Šibtum, the king expresses concern regarding another infected servant who has been freely interacting with the personnel:

Now command that no one will drink from a cup that she drinks from, nor sit in a chair in which she sits, nor sleep on a bed in which she sleeps![3]

The ancients did not know why some illnesses were contagious, and entertained multiple possibilities regarding the causes of disease, including demonic attack, witchcraft, or divine anger and curse. For example, the Shurpu incantations seek to treat a severely ill person by addressing numerous possible causes, including contact with an “accursed” (tamû) person:

The curse (māmītu) of talking to an accursed man,
The curse of eating an accursed man’s food,
The curse of drinking an accursed man’s water,
The curse of drinking an accursed man’s left-overs.[4]

Some of these combine the fear of curse with elements of physical contact (food, water, etc.), while others (talking) do not.

Touched by God and Touched by Illness

ANE texts refer to plague as a “devouring by the god” or as the god’s “placing the hand” or “touching” (ilappat /ulappat) the affected region, implying that they understand the cause to be divine. At the same time, these letters describe responses to these plagues that range from containing individual cases through quarantine to mass exodus from affected (laptum, literally “touched”) cities. In other words, even if the ultimate cause of an illness was the divine touch, the effects of infectious illnesses could be transferred from person to person.

Like the Mesopotamian sources, the Bible refers to mass afflictions as manifestations of the “hand” of God. Similarly, they use the root נ.ג.ע which can mean “touch,” “strike” or “afflict,” comparable to the Akkadian verb lapātu in the sources cited above. [5] A good example of this is the description of what happened to Pharaoh after he took Sarai:

בראשית יב:יז וַיְנַגַּע יְ־הֹוָה אֶת פַּרְעֹה נְגָעִים גְּדֹלִים וְאֶת בֵּיתוֹ עַל דְּבַר שָׂרַי אֵשֶׁת אַבְרָם.
Gen 12:17 But YHWH struck (נ.ג.ע) Pharaoh and his household with mighty plagues on account of Sarai, the wife of Abram.[6]

The derivatives of this verb include the piel verbal form used to describe God afflicting people and lands with disease (וינגע, e.g., Genesis 12:17; 2 Kings 15:5).

The verbal root נ.ג.ע, is also used in noun form to describe infectious diseases, especially the skin disease tzaraʿat:

ויקרא יג:ט נֶגַע צָרַעַת כִּי תִהְיֶה בְּאָדָם וְהוּבָא אֶל הַכֹּהֵן.
Lev 13:9 When a person has an affliction of tzaraʿat, it shall be reported to the priest.

This ambiguity between the “touch” of gods (divine punishment) and interpersonal contagion likely reflects the fundamental perception that external factors bring about disease and cause it to spread, even if it isn’t the same external factor doing both. In other words, a disease may start with a person being struck by a deity, but once one person contracts the disease, it can spread from that person to others. The “touch,” whether a gods or a person’s, is the catalyst.

The Root of Contagion

Notably, the English word contagion (Latin contagio) derives from com + tangere, meaning “touched with,” reflecting an intuition shared by ancient Mesopotamian, biblical, Latin and Greek authors.[7] They understood contagion was involved, even without knowing exactly how. British medical historian, Vivian Nutton, comments regarding the Greek and Latin evidence:

In all this it is perhaps foolish to seek to distinguish between degrees of propriety in the application of a metaphor, or to differentiate medical from non-medical. Many of those who talked of the contagion of illness or of heresy would not have been able to explain in what way they thought that the “common touch” worked, and few, if any, would have restricted the touch to the mere physical person-to-person transmission of a noxious substance. What mattered was the consequence, the “sharing” of the disease, rather than the action of touching itself.[8]

Tzaraʿat: The Paradigmatic Contagious Illness

As fear of contagion is a key concern in determining whether a person is unclean, the repeated close association of נֶגַע with tzaraʿat, appearing over sixty times in Lev 13–14 (!), makes intuitive sense. This disease, more than any other, was treated as contagious, as suggested by both biblical and Second Temple Period writings.[9] This is almost certainly the reason lepers were banished from the camp:

ויקרא יג:מה וְהַצָּרוּעַ אֲשֶׁר בּוֹ הַנֶּגַע בְּגָדָיו יִהְיוּ פְרֻמִים וְרֹאשׁוֹ יִהְיֶה פָרוּעַ וְעַל שָׂפָם יַעְטֶה וְטָמֵא טָמֵא יִקְרָא. יג:מו כָּל יְמֵי אֲשֶׁר הַנֶּגַע בּוֹ יִטְמָא טָמֵא הוּא בָּדָד יֵשֵׁב מִחוּץ לַמַּחֲנֶה מוֹשָׁבוֹ.
Lev 13:45 As for the one bearing tzaraʿat, his clothes shall be rent, his head shall be left bare, and he shall cover over his upper lip; and he shall call out, ‘Unclean! Unclean!’ 13:46 He shall be unclean as long as the disease is on him. Being unclean, he shall dwell apart; his dwelling shall be outside the camp.”[10]

We see this again in the narrative of the four “lepers” banned from the city (2 Kgs 7), which must be understood as reflecting a fear of contagion.

“Unclean! Unclean!” Wretched Lepers outside Jerusalem. Date: 1896. Thomas Fisher Rare Book Library, University of Toronto. Flickr

Infection and Spreading

Spreading of disease is not only about person to person, but even within one person. Think of the English term “infection,” which can be used to describe the multiplication of bacteria within a person (e.g.: “his wound got infected”) and the interpersonal spread of disease (what we call “infectious disease”).[11] Indeed, the key diagnostic characteristic of a נֶגַע is its spreading, as expressed by the verb פ.ש.ה, which appears 22 times in the chapters about tzaraʿat and nowhere else in the Bible:

ויקרא יג:ו וְרָאָה הַכֹּהֵן אֹתוֹ בַּיּוֹם הַשְּׁבִיעִי שֵׁנִית וְהִנֵּה כֵּהָה הַנֶּגַע וְלֹא פָשָׂה הַנֶּגַע בָּעוֹר וְטִהֲרוֹ הַכֹּהֵן מִסְפַּחַת הִוא וְכִבֶּס בְּגָדָיו וְטָהֵר: יג:ז וְאִם פָּשֹׂה תִפְשֶׂה הַמִּסְפַּחַת בָּעוֹר אַחֲרֵי הֵרָאֹתוֹ אֶל הַכֹּהֵן לְטָהֳרָתוֹ וְנִרְאָה שֵׁנִית אֶל הַכֹּהֵן: יג:ח וְרָאָה הַכֹּהֵן וְהִנֵּה פָּשְׂתָה הַמִּסְפַּחַת בָּעוֹר וְטִמְּאוֹ הַכֹּהֵן צָרַעַת הִוא:
Lev 13:6 On the seventh day the priest shall examine him again: if the affliction has faded and has not spread on the skin, the priest shall pronounce him clean. It is a rash; he shall wash his clothes, and he shall be clean. 13:7 But if the rash should spread on the skin after he has presented himself to the priest and been pronounced clean, he shall present himself again to the priest.13:8 And if the priest sees that the rash has spread on the skin, the priest shall pronounce him unclean; it is tzaraʿat.

The presence or absence of spreading is what determines whether or not the condition is diagnosed as “impure.”[12]

What About Tum’ah?

Matters become tricky when we attempt to understand the term (ט.מ.א), a word whose etymology remains obscure, and which is generally translated as impure. The term tum’ah is broad, reflecting the idea that a defiling substance or force can be transferred from one person or thing to another, even if it is not visible.

It can be applied to conditions we would consider illness (leprosy, gonorrhea) as well as conditions we would consider natural (menstrual bleeding, ejaculation). Not surprisingly, the types of pollution that were associated with disease were treated more seriously.

Biblical scholars have often underestimated the relationship between pollution and infectious disease, viewing it as an exclusively “religious” phenomenon. However, cross-cultural examples, including those from the ancient Near East, show that the terminology of (im)purity was frequently used to describe the symptoms of disease.

For example, in relation to the Mesopotamian skin disease saḫaršubbû, the curability—or more commonly, the incurability—of this disease was designated with the idiom of purification (ebbu/ ebēbu), as in the following curse:

May Sîn (the moon god) cover his entire body with incurable saḫaršubbû so that he will not be pure/ healed (āy ibbib) until the end of his days![13]

This quote, and others like it, show that terms such as impure and pure are not confined to the cultic domain, appearing regularly in the context of disease and healing.[14] This is not really a contradiction. In twentieth century research, a sharp dichotomy can be found between materialistic explanations of impurity relating it to hygiene and critics of these attempts who appeal to symbolic interpretations (for example, that purity and impurity represent forces of life and death).[15] This dichotomy resulted from an anachronistic imposition of modern concepts of disease on the ancient textual evidence.[16]

Similarly, the roots ט.ה.ר and ט.מ.א have several usages that would correspond to a medical diagnosis, specifically whether the patient bears the disease in question and is hence “infected” or “ill,” or whether s/he does not and is therefore “uninfected,” “cured,” or “healthy.” Let us look at some examples, starting again with the tzara’at.

Pure or Impure as Medical Diagnoses

Leviticus 13 requires the priest to determine whether the person should be diagnosed with tzaraʿat, and this diagnosis has far-reaching legal and ritual ramifications. This usage is expressed repeatedly by the piel forms of these roots,[17] for example in verse 8:

ויקרא יג:ח וְרָאָה הַכֹּהֵן וְהִנֵּה פָּשְׂתָה הַמִּסְפַּחַת בָּעוֹר וְטִמְּאוֹ הַכֹּהֵן צָרַעַת הִוא.
Lev 13:8 And if the priest sees that the rash has spread on the skin, the priest shall pronounce him infected (ט.מ.א); it is tzaraʿat.[18]

A related usage is the use of the term “pure” in reference to a person who has healed. For example, the rules for the man with a discharge in Lev 15 read as follows:

ויקרא טו:יג וְכִי יִטְהַר הַזָּב מִזּוֹבוֹ וְסָפַר לוֹ שִׁבְעַת יָמִים לְטָהֳרָתוֹ וְכִבֶּס בְּגָדָיו וְרָחַץ בְּשָׂרוֹ בְּמַיִם חַיִּים וְטָהֵר.
Lev 15:13 When one with a discharge is cured (ט.ה.ר) of his discharge, he shall count off seven days for his cleansing (ט.ה.ר), wash his clothes, and bathe his body in fresh water; then he shall be clean (ט.ה.ר).

This verse employs the root ט.ה.ר in two distinct senses. The first designates the cessation of flow, enabling him to begin the seven-day process of cleansing or purification; the second appears at the end of this verse and designates this cleansing/purification. The first refers to the physiological situation which enables the purification to take place. The second refers to the status of cultic purity that results from the completion of the purification rites.

The Cleansing or Curing of Naaman

Tahor as an idiom for healing also appears in the story of Naaman, the Aramean general. After he is stricken with tzaraʿat, he is told that Israel has a prophet named Elisha who can cure him. He travels to Israel and finds Elisha, who tells him to dunk seven times in the Jordan River. Naaman defiantly asks in response:

מלכים ב ה:יב הֲלֹא טוֹב (אבנה) [אֲמָנָה] וּפַרְפַּר נַהֲרוֹת דַּמֶּשֶׂק מִכֹּל מֵימֵי יִשְׂרָאֵל הֲלֹא אֶרְחַץ בָּהֶם וְטָהָרְתִּי
2 Kgs 5:12 Are not the Amanah and the Pharpar, the rivers of Damascus, better than all the waters of Israel? I could bathe in them and be cured (ט.ה.ר)!

Anthropological Parallels

This association of impurity with the contagiousness of disease is the rule, not the exception. In his study of the East African Kikuyu tribes, anthropologist Louis Leakey (1903–1972) writes about the purification undergone by a patient following healing from the mūrimu-pollution left by smallpox:

Even after this, for the duration of one moon he had to keep to himself, sleep by himself, and eat by himself, after which he might resume normal life. Although the purification for a mūrimu was thus a ceremonial one from the Kikuyu point of view, it provided a reasonably good way of disinfecting and isolating a person who had a serious disease, until his freedom from it was certain.[19]

Rahul Peter Das, Professor of South Asian Studies at Martin Luther University (Halle-Wittenberg), draws a similar conclusion from classical Indian texts. He notes that for the avoidance of disease,

[T]he so-called ‘ritual purity’, so often mentioned in connection with India, makes eminent sense, though clearly the adjective ‘ritual’ is, in the light of what we have seen so far, quite out of place here.[20]

The medical anthropologist Edward Green has boldly stated this association in categoric terms:

Pollution… is not so mystical when examined closely. In the anthropological sense, pollution denotes a belief that people will become ill as a result of contact with, or contamination by, a substance or essence considered dangerous because it is unclean or impure.[21]

This down-to-earth approach to understanding impurity challenges the widespread use of expressions such as “religious” or “ritual” impurity to translate Hebrew ṭum’ah, which suggest that its implications were only for the sacred domain: entrance to the sanctuary and participation in cultic worship. Instead, the concerns surrounding ṭum’ah in ancient Israel do not appear to have been confined to the cult, but likely involved fear of contagion, at least in some, if not most, cases.

Emphasis on Sanctuary Defilement

Nevertheless, it remains significant that the purity laws of the Bible (attributed in modern biblical scholarship to the Priestly Source) emphasize the ramifications on defilement for the sanctuary.[22] For example, the laws of normal and pathological genital emissions conclude with the following exhortation, which also serves as the finale of the purity laws in Lev 11–15:

ויקרא טו:לא וְהִזַּרְתֶּם אֶת בְּנֵי יִשְׂרָאֵל מִטֻּמְאָתָם וְלֹא יָמֻתוּ בְּטֻמְאָתָם בְּטַמְּאָם אֶת מִשְׁכָּנִי אֲשֶׁר בְּתוֹכָם.
Lev 15:31 You shall set apart the Israelites from their impurities lest they die in their impurities by defiling my Tabernacle that is among them.

The rule for banishing severe impurity bearers from the camp in Num 5 has a similar emphasis:

במדבר ה:ב צַו אֶת בְּנֵי יִשְׂרָאֵל וִישַׁלְּחוּ מִן הַמַּחֲנֶה כָּל צָרוּעַ וְכָל זָב וְכֹל טָמֵא לָנָפֶשׁ. ה:ג מִזָּכָר עַד נְקֵבָה תְּשַׁלֵּחוּ אֶל מִחוּץ לַמַּחֲנֶה תְּשַׁלְּחוּם וְלֹא יְטַמְּאוּ אֶת מַחֲנֵיהֶם אֲשֶׁר אֲנִי שֹׁכֵן בְּתוֹכָם.
Num 5:2 Command the Israelites to remove from the camp any leper or gonorrhoeic and anyone defiled by a corpse. 5:3 Remove males and females alike; put them outside the camp so that they will not defile the camp where I reside in their midst.[23]

This verse more than any other captures the anomaly that the banishment of diseased persons from the settlement, which otherwise would be interpreted as reflecting a need to quarantine infectious individuals, was here reinterpreted in terms of the need to distance impurity from the site of the divine presence.

Bringing Contagion Under God’s Hegemony

Based on the rhetoric of the purity laws and their emphatic focus on the sanctuary, it is understandable that many modern scholars have inferred that purity was only a concern in relation to the sacred domain, as Talmudic scholar Vered Noam (Tel-Aviv University) notes: “[I]n the absence of sanctity, impurity has virtually no meaning or existence.”[24]

Admittedly, one should not read the book of Leviticus as instructions how to avoid infection, nor should we view Moses as playing the role of public health commissioner. Nevertheless, one only needs to scratch the surface of these texts to reveal that the explicit rhetoric conceals a more down-to-earth role for purity in ancient Israel, related to the control and treatment of contagious disease, an impression reinforced by cross-cultural parallels.

If so, the Priestly Source’s near total absorption of impurity into the realm of the cult constituted nothing less than bringing the chaotic world of disease under the hegemony of God, removing the need for exorcistic rites.[25] In short, tum’ah is indeed religious, but this religion is not “out there” in the heavens. No, the thing is very close to you (Deut 30:14). Maybe too close.


April 11, 2019


Last Updated

April 9, 2024


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Dr. Yitzhaq Feder is a lecturer at the University of Haifa. He is the author of Blood Expiation in Hittite and Biblical Ritual: Origins, Context and Meaning (Society of Biblical Literature, 2011). His most recent book, Purity and Pollution in the Hebrew Bible: From Embodied Experience to Moral Metaphor (Cambridge University Press, 2021), examines the psychological foundations of impurity in ancient Israel.