The first mitzvah we have in the Torah is the mitzvah of peru urevu. After creating Adam and Chavah, Hashem instructed: פרו ורבו ומלאו את הארץ וכבשה - “be fruitful and multiply, replenish the earth, and conquer it.” (Bereishis 1:28). Although it was initially issued to Adam and Chavah, the instruction was not pronounced as a personal obligation, but as applying to all of humankind and remains a permanent mitzvah for all generations (see Rambam Sefer HaMitzvos, Aseh 212 and Sefer HaChinuch, Mitzvah 1).
Consequently, we will take this week’s opportunity to discuss the fascinating topic of the mitzvah of peru urevu, the mitzvah to have children.
The Basic Mitzvah
The Mishnah (Yevamos 61b) records a dispute concerning the basic parameters of the mitzvah to have children: “A person may not neglect procreation unless he has children. Beis Shamai say: two males; Beis Hillel say: one male and one female, as it says (Bereishis 5:2): He created them male and female.”
The Gemara explains the rationale for the two positions: “What is the reason for Beis Shamai’s position? We learn from Moshe, as it says (Divrei HaYamim 1:29), ‘The sons of Moshe: Gershom and Eliezer.’ And the reason for Beis Hillel? We learn from the creation of the world. Why does Beis Shamai not learn from the creation of the world? We do not learn what is possible from what is impossible.”
Rashi explains that it was impossible to create the world with only two males, since they could not reproduce. However, now that there is a large population and no lack of women in the world, the mitzvah can be defined as having two sons.
The halachah follows the opinion of Beis Hillel, and one fulfills the mitzvah by having a boy and a girl, thereby emulating Hashem’s creation of the world. The Rambam (Hilchos Ishus 15:4) thus rules as follows: “How many children must a man have for this commandment to be fulfilled? A male and a female, as it says: ‘male and female he created them.’”
Purpose of the Mitzvah
The Rambam adds a number of important halachos which indicate that the purpose behind the mitzvah of peru urevu is to enable continuity.
“If the son or the daughter is not able to procreate, he has not fulfilled the commandment.”
If a person’s children are themselves unable to bear children, he does not fulfill the mitzvah. Moreover, if a person’s children die, he does not fulfill the mitzvah – unless he has grandchildren (15:5):
The Chinuch learns the mitzvah of peru urevu from the pasuk in this week’s parsha: ויברך אותם אלקים ויאמר להם אלוקים פרו ורבו – “And G-d blessed them, and said to them ‘be fruitful and multiply’” (Bereishis 1:28). However, the Achronim ask why the Chinuch doesn’t bring the pasuk in Parshas Noach of: ואתם פרו ורבו שרצו בארץ ורבו בה – “And you shall be fruitful and multiply, swarm the land and fill it” (Bereishis 9:7), which is the pasuk the Rambam in Sefer HaMitzvos brings. Moreover, the Ramban in Parshas Noach writes that the pasuk in Bereishis is just a berachah, whereas the pasuk in Parshas Noach is the actual source for the mitzvah.
“If he had children and they died and left children of their own, he has fulfilled the commandment of pirya verivya, since grandchildren are like children. In what situation [is this true]? If the grandchildren are both male and female and they were born to his children who were both male and female. But if he had a son and daughter and they died and one of them left a son and a daughter, then he has still not fulfilled the commandment.”
Although the words recorded in our parsha are spoken to Adam and Chava, and not to the Jewish people, the basic rationale of populating the world and preserving the species remains. The Rambam thus writes (Sefer HaMitzvos 212):
“The command which we were commanded to be fruitful and multiply and to intend for the preservation of the species, and this is the commandment of pirya verivya.”
The Sefer HaChinuch (Mitzvah 1) likewise states: “One who violates [peru urvu] has violated a positive commandment and his punishment is very great for he has shown that he does not want to complete G-d’s wishes to populate his world.”
A Passive Mitzvah?
The terminology employed in describing the mitzvah to beget children is unusual. Rather than speaking of a positive action, the Mishnah states the obligation of peru uervu in the negative: לא יבטל אדם מפריה ורביה אלא א"כ יש לו בנים - “A person may not neglect procreation unless he has children.” The mitzvah is described as the removal of a prohibition (of neglecting procreation) rather than the fulfillment of an obligation.
The Rambam begins his Halachos of peru urevu with a positive instruction: “[A person] is obligated to have relations [on a regular basis] until he has children.” However, the Rambam continues with a passive form that is unique to this mitzvah: “How many children must a man have for this commandment to be fulfilled?”
Following similar lines, the Sefer HaChinuch writes “How many children must he have for him to be exempt,” focusing on the removal of the obligation rather than its fulfillment.
It appears that this terminology derives from the fact that there is no action or sequence of actions which necessarily fulfills peru urevu. The same actions sometimes result in fulfillment, and sometimes do not – the outcome is beyond the ability of man to determine.
Moreover, even one who fulfills peru urevu cannot do so in a conclusive manner, for it is possible that his children will die childless. A person does what he can, and whether or not those actions result in fulfillment remains out of his control. This is perhaps the reason for the unusual terminology used by Chazal and by later authorities in describing the mitzvah.
Indeed, in view of its special nature, authorities dispute the precise definition of the mitzvah.
Mitzvah at Childbirth
Based on the fact that the mitzvah depends on the continued life (and fertility) of a person’s children, the Minchas Chinuch (1:14) writes that the mitzvah of childbearing is essentially different from other mitzvos:
“It seems clear that this mitzvah is not like other mitzvos. The mitzvos of lulav, matzah, and so on, do not have a continued duration. Rather, immediately after performing the mitzvah he has fulfilled his obligation. However, this mitzvah is different, in that the act of procreation is not the mitzvah itself, and is rather a preparation for a mitzvah (hechsher mitzvah), the main part of the mitzvah being actually having children. The obligation is incumbent at every moment, and if the children die a person has not fulfilled his obligation from that time and onward. This is obvious.”
Based on this understanding, the Minchas Chinuch explains the ruling implied by the Rema (Even HaEzer 1:6, based on the Rashba, Yevamos 22b) that the mitzvah of bearing children is fulfilled even with a mamzer child. The simple wording implies that this is true even if the child is the product of a forbidden relationship (the Minchas Chinuch proceeds to question this ruling, and cites sources that dispute it).
Although the general principle is that a mitzvah cannot be performed through a forbidden act (mitzvah haboh b’aveirah), in this case the forbidden act (of marital relations) is not the mitzvah itself, but only a preparation for the mitzvah. The transgression therefore does not affect the fulfillment of the mitzvah.
The Minchas Chinuch further relies on this approach to the mitzvah to explain how it is possible that a ger [convert], who had children as a non-Jew and later converted, fulfills the mitzvah with his original children (according to the Rambam the children also have to become gerim) and is not obligated to have children as a Jew. Although for regular mitzvos this is not the case – a mitzvah performed in a state of halachic exemption from the mitzvah is not a valid performance – the case of peru urevu is different, because the essence of the mitzvah is not the act of procreation, but rather actually having children.
Mitzvah of Marital Relations
The Minchas Chinuch proceeds to point out that an early source – Tosfos (Bava Basra 13a) – states quite clearly that the mitzvah of peru urevu is fulfilled at the time of marital relations, and not at the time of childbirth. Due to this proof, the Minchas Chinuch leaves the debate as requiring further scrutiny.
The Gemara cites the din, that if there was a slave owned by two masters, and one of them freed him and one didn’t, and so he now has the din of a half slave, half free man (chatzi eved, chatzi ben chorin) we force the master who still owns him to free him, to help ensure the slave can fulfill the mitzvah of peru urevu. As long as the slave is a half slave, half free man, he can’t live with anyone, there is a prohibition for a slave to live with a non-slave, so he can’t live with a non-slave, however, since he is also half free, he can’t live with a slave either. Tosfos asks, why don’t we apply the rule of aseh docha lo saseh [positive commandment overrides a negative commandment] and say that the aseh of peru urevu overrides the prohibition of lo yihyeh kodesh [the prohibition of a slave and non-slave living together]? Tosfos answers, that we can’t apply the rule of aseh docha lo saseh, as the aseh and lo saseh aren’t fulfilled at the same time, the lo saseh is transgressed at the beginning of marital relations, whereas the fulfilment of the aseh of peru urevu is only fulfilled at the end.
It’s clear from Tosfos that the mitzvah of peru urevu isn’t dependent on having children, as if that was the case Tosfos could have made a much better argument: Who says he will have any children, perhaps he won’t fulfil the aseh at all.
Although the above Tosfos isn’t enough to make the Minchas Chinuch retract from his opinion, R’ Moshe Feinstein maintains it is. R’ Moshe (Igros Moshe, Even HaEzer 2:18) writes: “It is not logical to believe like the Minchas Chinuch that the mitzvah is not on an action. The essence of the instruction of peru urevu cannot be actually bearing children, because this matter is beyond a person’s control. Rather, the mitzvah and obligation is to have marital relations with his wife, from which it is possible to procreate.”
Based on the aforementioned Tosfos, and in keeping with the wording of the Mishnah [and the Rambam, as noted above], Rav Moshe explains that the mitzvah involves nothing beyond the act of marital relations, which is in a person’s control. Any later childbirth is not the mitzvah per se, but rather an exemption: Once a person has children, he is no longer obligated in peru urevu.
The Role of Women in the Mitzvah
Although there are minority opinions that maintain that women are included in the obligation of peru urevu (see Yerushalmi, Yevamos 6:6) – just as Chavah was included in the original Divine instruction of procreation – the dominant position of the Gemara and of later authorities is that women are exempt from the mitzvah. This exemption seems odd: Surely women play a central role – the central role, in fact – in childbearing, and if anything, the full brunt of the mitzvah ought to fall on them. What are the reasons behind their exemption?
The Gemara (Yevamos 65b) explains that the pasuk, “Be fruitful and multiply,” does not apply to women, in as much as they are not included in the command at the end of the pasuk: “Fill the earth and conquer it.” Women are not being commanded here because, as the Gemara explains, “It is in man’s nature to conquer, and not in woman’s nature to conquer.”
The question is, the Gemara in Kiddushin (41a) teaches: A man can carry out the mitzvah of kiddushin [getting married], either himself, or with an agent. Similarly, a women may accept kiddushin, either by herself or with an agent. The Gemara asks: If she can use an agent, certainly she can do it herself, what is the novelty? And the Gemara answers: מצוה בה יותר מבשלוחה – “It’s better to carry out the mitzvah oneself than to use an agent”.
From the above Gemara it seems that there is a mitzvah for a woman to get married, so we see a woman has a mitzvah of peru urevu? The Ran answers, although women are exempt from the mitzvah, they have an integral part of the mitzvah, for without their partnership men would of course be unable to fulfill the mitzvah.
The Chiddushei Anshei Shem on the Ran asks, that we don’t find anywhere women have a mitzvah to help their husbands fulfill the mitzvah of peru urevu.
The L’Horas Nossan (6:105:2) answers the Ran based on a Rosh in Berachos (20b). The Gemara teaches: כל ישראל ערבים זה לזה – “all of Klal Yisroel are responsible for each other”. The Rosh explains, Klal Yisroel are responsible to help each other carry out mitzvos, and to stop each other from doing any aveiros. Women, however, are not included in the above. The Maharit (Kiddushin 71b) explains, women are excluded as they can’t stop people from doing aveiros as they must serve their husbands. Based on the above, since one can’t fulfill peru urevu without the help of a women, in regard to such a mitzvah women are included in the arvus [being responsible for others] and they have to do what they can to help the men fulfill the mitzvah. In regard to such a mitzvah we can’t say they are exempt because they have to serve their husbands, on the contrary they must serve their husbands, therefore, they must help them fulfil the mitzvah.
A Novel Approach from the Meshech Chochma
Rabbi Meir Simcha of Dvinsk in his Mesech Chochma (Bereishis 9:7) offers a novel approach to explain why women are exempt, he writes: “The reason the Torah exempted women from peru urevu and obligated only men, is because G-d’s Law and the Torah’s ways are, “ways of pleasantness and all of her paths are peace” (Mishlei 3:17), and the Torah did not burden a Jew with an obligation that he is physically unable to handle... Therefore, regarding women, who are endangered during pregnancy and childbirth... the Torah did not obligate them to procreate.”
Women, according to this approach, would be obligated in the mitzvah if it did not entail physical danger to them. Because of the risk involved in childbirth, women are exempt from the obligation.
From What Age Does the Mitzvah of Peru Urevu Start, and Why?
The Rambam (Hilchos Ishus 15:2) writes: “A man is commanded in the mitzvah of peru urevu, not a woman. From when is a man obligated in this mitzvah? From seventeen”. The Maggid Mishnah brings a few different versions of the Rambam, some say seventeen and some say eighteen. The Maggid Mishnah cites the Mishnah in Avos (5:21) which says: “eighteen is the age to get married”, and he explains, even if the Rambam says seventeen, he means after seventeen complete years have passed.
The Levush (Even HaEzer 1:3) says, the pasuk writes: לא טוב היות אדם לבדו – “It’s not good for man to be alone” and the gematria [numerical value] of the word טוב is seventeen, so we see that once one turns seventeen it’s no longer good for him to be alone.
However, Rashi on the Mishnah in Avos writes, that it says eighteen times the word אדם from the beginning of Bereishis until the pasuk of, כי מאשה לקחה זאת (Bereishis 2:23), which talks about the creation of Chavah, and hence the first shidduch, so we see one should get married at eighteen.
We see that the age for when the mitzvah of peru urevu starts is either seventeen or eighteen, the question is, why should the mitzvah of peru urevu be different to all other mitzvos in the Torah which start at thirteen?
The Chelkas Mechokek (Even HaEzer 1:2) answers, that one must learn before he gets married, and the Mishnah in Avos says the time to start learning is fifteen. Even though we normally find that the time it takes to learn is at least five years, the Shulchan Aruch HaRav (Hilchos Talmud Torah 3:1) explains, that after one gets married for the first two or three years, one is still able to learn as for the first few years, one’s family is small and easy to look after.
The Rambam adds: “if one reaches twenty and still hasn’t married he is in violation of a mitzvas aseh [positive commandment]”. The source for the above is the Gemara in Kiddushin (29b) which says, “Until one turns twenty, Hashem sits and waits to see who one will marry, once he turns twenty then Hashem says his bones shall be overturned.”
It’s brought down in the name of the Steipler (in Sefer Toldos Yaakov pg. 335), that the above Gemara only refers to a case of someone who didn’t do anything about getting married, if one tried but wasn’t yet successful in finding a shidduch then it doesn’t apply.
The Torah Temimah (Bereishis 1:28:65) offers another approach to explain why this mitzvah only starts from age eighteen, and why one only violates a mitzvas aseh when he turns twenty. Based on the aforementioned Gemara in Yevamos (65b) which says women are exempt as it says in regard to the mitzvah of peru urevu “fill the earth and conquer it”, and it’s not the way for women to conquer, the Torah Temimah explains, the obligation to go out to war only starts from age twenty, therefore, one only violates a mitzvas aseh when he turns twenty.
(The above write-up is based on Teshuvos written by R’ Yehoshua Pfeffer and R’ Yom Tov Sanger)
