Purpose of the Laws of Hybrids/2

Laws of Hybrids – כלאיים

Exegetical Approaches

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Preserving Natural Order

When Hashem created the world, He made each plant and animal according to its species, and mandated that each species should reproduce according to it own kind. Crossbreeding and other mixing of species is prohibited because it goes against Hashem's plan of creation and the natural order He set in the world.

Sources:PhiloThe Special Laws IV: 208-217About Philo #1, RashbamVayikra 19:19About R. Shemuel b. Meir, Ibn EzraVayikra 19:19Devarim 22:9-12About R. Avraham ibn Ezra, R. Yosef Bekhor ShorVayikra 19:19About R. Yosef Bekhor Shor, ChizkuniVayikra 19:19Devarim 22:9-11About R. Chizkiyah b. Manoach, RambanVayikra 19:19Devarim 22:10About R. Moshe b. Nachman, R. BachyaVayikra 19:19Devarim 22:10About R. Bachya b. Asher, TurLong Commentary Vayikra 19:19About R. Yaakov b. Asher, R. Yosef ibn KaspiVayikra 19:19About R. Yosef ibn Kaspi, RalbagVayikra 19:19About R. Levi b. Gershom, R. Avraham SabaTzeror HaMor Vayikra 19:9About R. Avraham Saba (Tzeror HaMor), MaharalGur Aryeh Vayikra 19:19About R. Judah Loew of Prague, R. S.R. HirschVayikra 19:19About R. Samson Raphael Hirsch, R . David Zvi HoffmannVayikra 19:19Devarim 22:9About R. David Zvi Hoffmann

What is wrong with mixing species? All these sources emphasize that since Hashem created each species "according to its own kind," mankind, too, must not mix species. Yet, they disagree regarding the specifics of why this is problematic:

• Hubris – R"Y Bekhor Shor points out that there is a certain hubris in crossbreeding, as if one is trying to turn one's self into Creator, usurping the role of God. Ramban adds that in so doing it is as if one is questioning the perfection of Hashem's world and suggesting that it needs improvement.¹
• Harming creation – Both R"Y Bekhor Shor and Ramban² further point out that Hashem created a world that can perpetuate itself, but hybrids can't reproduce on their own. As such, in creating such hybrids, man reduces the good inherent in Hashem's creation.³
• Denial of Hashem – By acting contrary to Hashem's creation, it is as if one is denying Hashem's role as Creator.  R. Hirsch emphasizes that when observing the mitzvot of kilayim, on the other hand, one recalls the laws of nature set by God, and hence, Hashem Himself. The reminder is, thus, ever present throughout one's day: when one is engaged in raising of livestock, working the land, working with animals, and even when getting dressed.

Reminder of one's assigned place and purpose – R. Hirsch adds another positive aspect to the prohibition.  In remembering that all is created "according to its own kind" man is supposed to recall that he, too, has an assigned, unique task in life - keeping Hashem's Torah.

Crossbreeding vs. Sowing – Even though planting seeds of different species one next to another will not create a cross-breed, R"Y Bekhor Shor claims that it is prohibited as a precaution, since it is possible that accidentally the mixed seeds will combine and create a new plant.⁴ Rashbam, Ibn Ezra and R. Hirsch, instead, assume that the action is prohibited since, regardless of the ability to create a hybrid, it serves as a symbolic reminder that mixing species goes against Hashem's creation.

"שַׁעַטְנֵז" – These commentators disagree whether this commandment is related to the other prohibitions of mixing species or if it is prohibited for different reasons:

• Connected – Rashbam suggests that shatnez is simply a variation of the prohibition against making hybrids. Wool is a product of the animal kingdom, while linen emerges from plants and so the prohibited mixture similarly highlights that mixing of species is not desired and opposes Hashem's plan for creation. R. Hirsch adds that since man's clothing symbolizes man's inner essence, Hashem tells him not to wear a mixture of "animal" and "vegetable".  Man is supposed to be above both of these, not a hybrid of the two.
• Unconnected – R"Y Bekhor Shor, in contrast, assumes that shatnez is its own unique commandment.  It is found in the same verse as the laws of kilayim of animals and plants only due to the fact that both are prohibited mixtures. According to him, shatnez is prohibited because priestly garments were uniquely made from a mixture of wool and linen and such clothing is reserved for their use.  Wearing similar garments would be like using the scepter of a king, an object which is sacred to him and off-limits to anyone else.

"לֹא תַחֲרֹשׁ בְּשׁוֹר וּבַחֲמֹר יַחְדָּו" – These commentators disagree whether this commandment is related to the other prohibitions of mixing species or if it is prohibited for different reasons:

• Connected – R"Y Bekhor Shor and Ramban⁵ assert that plowing with an ox and donkey is prohibited as a precaution against crossbreeding.⁶  Rashbam and  R. Hirsch, instead, maintain that the prohibition simply reminds man of Hashem's desire that everything be created "according to its own kind", even if there is no fear of an actual cross-breed.
• Unconnected – Ibn Ezra and Chizkuni disconnect this prohibition from those of kilayim, suggesting that it relates instead to those laws regarding care of animals and not causing them distress.  Since the two animals have different strengths, it is unfair to the weaker animal to work them together.⁷

Meaning of "כִּלְאָיִם" – Ibn Kaspi suggests that "כִּלְאָיִם" relates to the verb "כלא"  which means to restrain or withhold.  The laws are so called because the plants and animals are being restrained from mixing with unlike species.

Exceptions – There are two exceptions to the laws of shatnez; Rabbinic law mandates that both the priestly garments and tzitzit may be made of a mixture of wool and linen.

• According to those who suggest that shatnez is no different than the other laws of kilayim, it is not clear why these exceptions should be made.
• According to R"Y Bekhor Shor, though, the exceptions are very understandable, as the entire reason for the prohibition of shatnez is that laymen not wear garments reserved for the priests.  Since tzitzit has been understood to be  as a symbol that all of Israel should strive to be a "kingdom of priests", this is the one mixed garment that laymen, too, can wear.

Biblical Parallels – R. Hirsch maintains that the prohibition against mixing milk and meat shares the same reasoning as the laws of kilayim.  It, too, is meant to remind man of the laws of "each according to its own kind" and Hashem's role as Creator.

"אֶת חֻקֹּתַי תִּשְׁמֹרוּ" – R. D"Z Hoffmann, following the Yerushalmi,⁸  suggests that these laws are introduced by the statement "אֶת חֻקֹּתַי תִּשְׁמֹרוּ" because they are enacted to ensure that the laws of nature (חוקי הטבע) remain intact.

Distancing from Idolatry

The prohibitions were instituted as a reaction to idolatrous customs, in an effort to keep the nation from imitating them.

Sources:RambamMoreh Nevukhim 3:37About R. Moshe b. Maimon, ShadalVayikra 19:19About R. Shemuel David Luzzatto

Grafting plants and sowing mixed seeds – Rambam asserts that certain idolatrous and superstitious rites of the Gentiles entailed the grafting of plants and sowing of diverse seeds, often accompanied by illicit sexual acts.  To distance the nation from such idolatry, Torah prohibited all similar mixtures.

Shatnez – Rambam states that it was the custom of idolatrous priests to wear wool and linen garments, and as such it is forbidden for Israelites to imitate them.

Exceptions – The fact that priestly garments are made of wool and linen is very difficult for Rambam.  One would have thought that their clothing especially should be made differently from those of the idolatrous priests.

Crossbreeding animals and mixed plowing – Shadal suggests that these laws, too, were likely idolatrous practices. Rambam, though, maintains that these prohibitions are distinct, related to a desire to distance man from enagiing in sexuality.⁹

Context – Rambam asserts that many of the laws in this section of the chapter, such as the laws of Orlah, eating on blood, divination, or cutting the skin in mourning, are similarly aimed at distancing one from the customs and idolatrous rites of foreign cultures. As such, the context would support this understanding of the reason for the prohibition.

"אֶת חֻקֹּתַי תִּשְׁמֹרוּ" – This position could suggest, as does R. D"Z Hoffman, that "חקים" refer to laws between man and Hashem and therefore appropriately introduce the laws of kilayim, which aim at distancing idolatrous practices.

Caring for the Land & Animals

Mixing of species harms one or both members of the mixture, and in the case of produce, also the land in which they are sown.

Sources:PhiloThe Special Laws IV: 208-217About Philo #3, Josephus4 8:114 8:20About Josephus Antiquities of the Jews #1,

Sowing mixed seeds – Philo maintains that when sowing seeds of different species together, one species takes nourishment away from the other, weakening it and perhaps causing it not to bear fruit at all.  Moreover, planting two crops of diverse type on the same ground will exhaust the land.  This is problematic both due to the harm it causes the land and because it betrays a covetous nature and lack of self-control, as one seeks to squeeze forth from the land more than it would naturally produce.

Plowing with mixed animals – Plowing a field with animals of different strengths is not fair to the weaker animal who will become exhausted as it attempts to keep up with the superior power of the stronger animal.

Shatnez – This prohibition has been understood in two ways, both related to the injustice incurred when the strong oppress the weak:¹⁰

• Philo asserts that since wool and linen are of different strengths, combining the two causes the weaker material to tear.
• Rav Kook suggests, instead, that the law was instituted to teach mankind sensitivity toward animals. When shearing wool, one is in essence robbing it from the innocent sheep. Linen, in contrast, is acquired by harming none. Since utilizing the flax plant and sheep are not morally equivalent, the Torah seeks to distinguish between the two and thereby highlight that animals are not inanimate objects like plants, and we should care about their welfare.

Cross-breeding animals – These sources do not explicitly address this prohibition, but might suggest that when cross-breeding, the less dominant animal is taken advantage of, as its unique qualities are lost in the newly created hybrid.

Biblical parallels – These laws can be compared to other laws instituted for the welfare of animals and land:

• Shemittah – Philo compares the prohibition against sowing mixed seeds to the prohibition of working the land during the sabbatical year which similarly is meant to prevent the land from growing exhausted. For elaboration of this understanding of the Sabbatical year, see Rambam's opinion in Purpose of Shemittah.
• Animal welfare –

Context – Devarim 22

Preventing Inappropriate Unions

The prohibition against mixing species relates to concerns regarding sexuality and inappropriate pairings.

Sources:Philo The Special Laws IV: 203-217About Philo#1, Josephus4 8:114 8:20About Josephus Antiquities of the Jews #2, RambamMoreh Nevukhim 3:49About R. Moshe b. Maimon,¹¹ Akeidat YitzchakVayikra Peirush 19About R. Yitzchak Arama #1

Illicit Unions

• Preventing illicit unions – Philo, Josephus, and Akeidat Yitzchak suggest that by banning inappropriate pairing of animals,¹² seeds, and even materials for clothing, the concept that inappropriate coupling is wrong will become so ingrained in mankind that he will naturally refrain from illicit relations and inappropriate unions such as bestiality, adultery and the like.
• Mitigate sexuality – Rambam maintains, instead, that crossbreeding is a degraded act in and of itself, as it entails that man physically intervene to cause two animals to copulate. Since the Torah wants to reduce one's indulging in sexual acts, it prohibits not only engaging in certain acts of cohabitation, but also watching animals unite, and certainly forcing them to copulate.

Shatnez – It is questionable whether the prohibition against mixing wool and linen is really similar enough to "coupling" to serve as a safeguard and preventive measure.  This question is likely what prompts each of these sources to suggest additional reasons for the prohibition. Akeidat Yitzchak, however, suggests that the very fact that these laws restrict man, teaches him self control.

Context – These sources might suggest that in Vayikra the command is juxtaposed to the prohibition against having relations with a maidservant who has been pledged to marry another (שפח חרופה) because both concern teaching man to resist his sexual desires and not have relations with inappropriate mates.

¹ The Maharal questions this, pointing out that in many areas of life man "improves" upon God's creation, turning wheat into flour, baking bread, and circumcising a child. He quotes Bereshit Rabbah 11:6 which states, "כָּל מַה שֶּׁנִּבְרָא בְּשֵׁשֶׁת יְמֵי בְרֵאשִׁית צְרִיכִין עֲשִׂיָה, כְּגוֹן הַחַרְדָּל צָרִיךְ לְמִתּוּק. הַתּוּרְמוּסִים צָרִיךְ לְמִתּוּק. הַחִטִּין צְרִיכִין לְהִטָּחֵן. אֲפִלּוּ אָדָם צָרִיךְ תִּקּוּן".  One might point to Hashem's command to Adam "מִלְאוּ אֶת הָאָרֶץ וְכִבְשֻׁהָ" as further evidence that we are actively meant to take the world and work with it to innovate and produce on our own.

² See also Ralbag.

³ Tzeror HaMor and R. Hoffmann also emphasize how Hashem had desired an ordered world, while mixing of species introduces chaos.

⁴ Ramban goes a step further, suggesting that seeds which are planted near each other might get nourishment from one another, changing their nature and form, so that the seeds themselves become as if they were cross-bred.

⁵ See also R. D"Z Hoffmann.

⁶ Ramban explains that it was common for a farmer to bring his work animals to breed together by the troughs.

⁷ Chizkuni, instead, explains that since an ox chews its cud while a donkey does not, it would cause suffering to the donkey to watch the ox chew while it has nothing to eat.

⁸ The Yerushalmi explains the word "חקים" to refer to the laws of nature:  "חוקים שחקקתי בהם את עולמי".

⁹ See below.

¹⁰ Josephus suggests that the law has its own unique  reasoning.  It is prohibited to wear a garment of wool and linen since such garments were designated for the priests alone.

¹¹ Rambam limits this reasoning to the prohibitions of cross-breeding and plowing with mixed species.  He maintains that the other laws of kilyaim relate to a desire to distance the nation from idolatry.

¹² They might suggest that plowing with a donkey and ox is banned lest a person come to cossbreed the animals.