Prompt
Sources: the Tanakh and the Talmud; answered in English in the Essay style.
THE ANSWER IN BRIEF
Piryah verivyah (פְּרִיָּה וּרְבִיָּה) is the rabbinic term for the commandment to be fruitful and multiply, derived directly from the biblical phrase peru urevu ("be fruitful and multiply") first spoken by God at creation [Genesis 1:28] and repeated after the Flood [Genesis 9:1, 9:7]. The Mishnah in Yevamot establishes that a man is obligated in this commandment while a woman, according to the majority view, is not [Yevamot 65b:3]. Beit Shammai and Beit Hillel dispute the minimum number of children required to fulfill it [Yevamot 61b:15]. The Talmud treats failure to fulfill piryah verivyah with striking severity, comparing the neglectful person to one who sheds blood [Yevamot 63b:16, 63b:19]. The commandment is understood as applying to Jews specifically, having been re-commanded at Sinai after its original address to the Noahides [Sanhedrin 59b:3].
BACKGROUND
The phrase piryah verivyah is a nominalized form of the biblical imperative peru urevu — "be fruitful and multiply" — and in rabbinic literature it functions as the technical name for a specific positive commandment (mitzvat aseh). The underlying biblical verses appear in Genesis at three distinct moments: first as a blessing to the animals [Genesis 1:22], then as a blessing and command to Adam and Eve [Genesis 1:28], and again as a command to Noah and his sons after the Flood [Genesis 9:1, 9:7]. The rabbinic tradition draws primarily on Genesis 1:28 and Genesis 9:7 for its legal analysis.
In the structure of rabbinic law, piryah verivyah sits in tractate Yevamot, which deals with levirate marriage and related family law. The commandment appears prominently in the sixth chapter of that tractate, where the Mishnah addresses who is obligated, what minimum fulfillment looks like, and what happens when a marriage produces no children. The topic recurs in Kiddushin (which treats the laws of betrothal and their gendered obligations) and in Sanhedrin (which asks whether the commandment applies to non-Jews).
Several key terms appear repeatedly in the sources. Mevattel (מְבַטֵּל) means "to neglect" or "to nullify" — the Mishnah says a man may not nullify himself from piryah verivyah [Jerusalem Talmud Yevamot 6:6:1]. Kiyyem (קִיֵּים) means "to fulfill" — the Talmud asks whether a convert who had children before conversion has fulfilled the commandment [Yevamot 62a:9]. Shofeikh damim (שׁוֹפֵךְ דָּמִים) — "sheds blood" — is the severe language used by Tannaim for one who neglects the commandment [Yevamot 63b:16]. Mema'et et ha-demut (מְמַעֵט הַדְּמוּת) means "diminishes the [divine] image," another grave characterization [Yevamot 63b:17].
The commandment is also notable for its gendered character. Unlike most positive commandments not caused by time (mitzvat aseh she-lo ha-zeman grama), for which women are generally obligated, piryah verivyah is one of the named exceptions in which women are exempt according to the majority rabbinic position [Kiddushin 34a:3, Eruvin 27a:6]. The reasoning for this exemption is derived exegetically from the specific wording of Genesis 1:28.
THE SOURCES
The Biblical Foundation
The commandment originates in three passages in Genesis. The first, addressed to the animals, reads: "And God blessed them, saying: Be fruitful and multiply, and fill the waters in the seas, and let the birds multiply on the earth" [Genesis 1:22]. This establishes the formula peru urevu as a divine blessing tied to abundance and filling the created world.
The second and legally decisive verse addresses the first human pair: "And God blessed them, and God said to them: Be fruitful and multiply, and fill the earth and conquer it, and rule over the fish of the sea and the birds of the sky and every living thing that moves on the earth" [Genesis 1:28]. This verse is the anchor for the rabbinic commandment, and its specific wording — particularly the word vekhivshuhah, "and conquer it" — becomes the basis for the Talmud's argument about who is obligated.
The third passage, addressed to Noah and his sons after the Flood, repeats the command twice: "And God blessed Noah and his sons, and said to them: Be fruitful and multiply and fill the earth" [Genesis 9:1], and again: "And as for you, be fruitful and multiply, swarm on the earth and multiply in it" [Genesis 9:7]. The Talmud in Sanhedrin uses these verses to argue about the commandment's scope for non-Jews.
Who Is Obligated: The Mishnah and the Gender Question
The Mishnah in Yevamot opens the legal discussion with a direct statement: "A man is commanded regarding piryah verivyah, but not a woman. Rabbi Yohanan ben Beroka says: Concerning both of them it says, 'And God blessed them and said to them: Be fruitful and multiply'" [Yevamot 65b:3]. The majority position, which becomes normative halakhah, restricts the obligation to men. Rabbi Yohanan ben Beroka dissents, arguing that the verse's plural address ("to them") obligates both sexes equally.
The Gemara immediately asks how the majority derives women's exemption [Yevamot 65b:4, 65b:5]. Rabbi Ile'a, citing Rabbi Elazar son of Rabbi Shimon, derives it from the word vekhivshuhah in Genesis 1:28 — "and conquer it." The argument, elaborated in Kiddushin, is that conquering is a male activity; since the verse links the command to procreate with the command to conquer, and women do not characteristically conquer, the obligation falls on men [Kiddushin 35a:2]. Rav Yosef offers a different derivation: Genesis 35:11 says "Be fruitful and multiply" in the singular masculine (preh urveh), not the plural (peru urevu), indicating a single individual — male — is addressed [Yevamot 65b:5].
The Talmud in Kiddushin acknowledges that piryah verivyah is an anomaly in the standard halakhic categories. It is a positive commandment not caused by time — which normally obligates women — yet women are exempt. This anomaly is cited as evidence that the general rule "all positive commandments not caused by time obligate women" does not hold without exception [Kiddushin 34a:3, Eruvin 27a:6]. Rabbi Yohanan's response is that one cannot derive law from general principles, even when exceptions are explicitly stated.
Minimum Fulfillment: Beit Shammai and Beit Hillel
The Mishnah states that a man may not neglect piryah verivyah unless he already has children, and then records a dispute: "Beit Shammai say: with two males, and Beit Hillel say: a male and a female, as it is stated: 'Male and female He created them'" [Yevamot 61b:15]. The Jerusalem Talmud records the same Mishnah with nearly identical language [Jerusalem Talmud Yevamot 6:6:1], adding that if a man married a woman and she remained with him ten years without giving birth, he may not remain idle from the commandment — implying he must take action, whether by divorcing and remarrying or by other means.
A baraita in the Babylonian Talmud adds a further position: "Rabbi Natan says that Beit Shammai say: the mitzva to be fruitful and multiply is fulfilled with two males and two females" [Yevamot 62a:6] — an even stricter reading of Beit Shammai's position. The normative ruling follows Beit Hillel: one son and one daughter.
Severity of Neglect: Blood and the Divine Image
The Talmud does not treat piryah verivyah as a minor procedural obligation. A baraita cited in the Gemara states: "Rabbi Eliezer says: Anyone who does not engage in the mitzva to be fruitful and multiply is considered as though he sheds blood, as it is stated: 'Whoever sheds the blood of man,' and it is stated near it: 'And you, be fruitful and multiply'" [Yevamot 63b:16, 63b:19]. The juxtaposition of Genesis 9:6 (the prohibition on bloodshed) with Genesis 9:7 (the command to multiply) is read as a textual signal: failure to produce life is morally equivalent to destroying it.
Rabbi Ya'akov adds a second dimension: "As though he diminishes the [divine] image, as it is stated: 'For in the image of God He made man,' and it is written near it: 'And as for you, be fruitful...'" [Yevamot 63b:17]. By not bringing new bearers of the divine image into the world, one effectively reduces the presence of God's image on earth.
Ben Azzai combines both charges: "As though he sheds blood and diminishes the image" [Yevamot 63b:17]. The Tosefta attributes a similar compound formulation to Rabbi Elazar ben Azariah: "Anyone who does not engage in piryah verivyah is as though he sheds blood and diminishes the image, as it is stated: 'For in the image of God He made man,' and it is written: 'And as for you, be fruitful and multiply'" [Tosefta Yevamot (Lieberman) 8:7].
The Talmud also connects piryah verivyah to messianic expectation: "Rabbi Assi said: The son of David will not come until all the souls in the [divine] storehouse (guf) are exhausted" [Yevamot 63b:16], citing Isaiah 57:16. The implication is that each birth releases a soul waiting to enter the world, and the fulfillment of piryah verivyah participates in the eschatological completion of creation.
Converts and Children Who Die
Two further discussions illuminate the commandment's scope. First, a dispute between Rabbi Yohanan and Reish Lakish: if a man had children before converting to Judaism, does he fulfill piryah verivyah with those children? Rabbi Yohanan says yes — "he had them" [Yevamot 62a:9]. Reish Lakish says no — "a convert who converts is like a newborn child" [Yevamot 62a:9], meaning his pre-conversion life is legally erased. The same dispute appears in Bekhorot, where Rabbi Yohanan's reasoning is given as the verse "He did not create it a waste; He formed it to be inhabited" [Bekhorot 47a:3] — a child born to populate the world counts regardless of the father's subsequent religious status.
Second, a dispute between Rav Huna and Rabbi Yohanan about children who die: Rav Huna says that if a man had children who subsequently died, he has fulfilled piryah verivyah. Rabbi Yohanan says he has not [Yevamot 62a:16]. The Talmud then cites a baraita: "Grandchildren are like children; if one of them died or was found to be a saris (a eunuch, incapable of reproduction), he has not fulfilled piryah verivyah" [Yevamot 62b:2]. This refutes Rav Huna's position.
The Commandment and Non-Jews
The Talmud in Sanhedrin addresses whether piryah verivyah remains a Noahide obligation. The argument runs: piryah verivyah was commanded to the sons of Noah [Genesis 9:7], so it should apply to all humanity. But the Talmud responds: "It was re-stated at Sinai: 'Go, say to them: Return to your tents' — it was said to Israel and not to the sons of Noah" [Sanhedrin 59b:3]. The re-statement at Sinai, the argument goes, transferred the commandment exclusively to the Jewish people, removing it from the Noahide code.
WHERE THEY AGREE AND DISAGREE
On the obligation of women: The Mishnah records a clear dispute. The majority view (unnamed in the Mishnah, but normative) exempts women; Rabbi Yohanan ben Beroka obligates them equally, reading the plural address of Genesis 1:28 as decisive [Yevamot 65b:3]. The Talmud in Kiddushin explores the technical halakhic consequence of both positions [Kiddushin 35a:1, 35a:2, 35a:3], but the tradition resolves in favor of the majority: women are exempt.
On the minimum required: Beit Shammai and Beit Hillel disagree on whether two sons, or one son and one daughter, suffices. A further Tannaitic source (via Rabbi Natan) gives Beit Shammai an even stricter position of two males and two females [Yevamot 62a:6]. Halakhah follows Beit Hillel: one son and one daughter.
On converts: Rabbi Yohanan and Reish Lakish disagree on whether pre-conversion children count. The Talmud does not formally resolve this dispute within the passages surveyed, though it presents both sides with their reasoning [Yevamot 62a:9, Bekhorot 47a:3].
On children who die: Rav Huna and Rabbi Yohanan disagree, but the baraita about grandchildren effectively decides against Rav Huna [Yevamot 62b:2].
On severity: The Tannaim agree that neglect of piryah verivyah is grave, but formulate it differently. Rabbi Eliezer focuses on the bloodshed analogy; Rabbi Ya'akov on diminishing the divine image; Ben Azzai and Rabbi Elazar ben Azariah combine both [Yevamot 63b:16–17, Tosefta Yevamot (Lieberman) 8:7]. These are complementary rather than contradictory positions, each drawing on a different textual juxtaposition within Genesis 9.
On applicability to non-Jews: The Talmud in Sanhedrin presents a clean argument that the commandment, though originally Noahide, was narrowed at Sinai to Israel alone [Sanhedrin 59b:3]. No counter-position is preserved in the sources surveyed.
CONCLUSION
Piryah verivyah is the rabbinic commandment to be fruitful and multiply, rooted in the biblical peru urevu of Genesis and given its legal shape in the Mishnah and Talmud. It obligates Jewish men to have at least one son and one daughter (following Beit Hillel), and it cannot be considered fulfilled if those children predecease the father or are constitutionally incapable of reproduction. Women are exempt by the majority halakhic view, derived exegetically from the wording of Genesis 1:28. The commandment carries exceptional moral weight in the tradition: neglecting it is compared by the Tannaim to shedding blood and diminishing the divine image. Its scope, its minimum requirements, and the status of converts' pre-conversion children are all subjects of named Talmudic disputes, most of which the tradition resolves — but not all. At its core, piryah verivyah is the legal expression of the imperative to continue human life as an act of religious and cosmic significance.
References
- Yevamot.65b:3
- Yevamot.61b:15
- Jerusalem Talmud Yevamot.6:6:1
- Yevamot.62a:6
- Tosefta Yevamot (Lieberman).8:7
- Yevamot.63b:16
- Yevamot.63b:19
- Yevamot.63b:17
- Yevamot.65b:4
- Genesis.1:22
- Genesis.9:1
- Genesis.9:7
- Genesis.1:28
- Sanhedrin.59b:3
- Yevamot.62a:9
- Bekhorot.47a:3
- Yevamot.62a:16
- Yevamot.62b:2
- Kiddushin.35a:1
- Kiddushin.35a:3
- Eruvin.27a:6
- Kiddushin.34a:3
- Yevamot.65b:5
- Kiddushin.35a:2
- Moed Katan.8b:11