If it was prohibited to kill animals from Adam to Noah how is it explained that Abel brought an animal from his flock as an offering to HaShem?
A very perceptive question. Many great Torah scholars have asked the same question!
There are three answers:
1) Zohar and many midrashim – It was an offering of wool only. His offering was what the Torah later calls the reishis hagaz – the offering of the first shearings of the flock. See Devarim (Deuteronomy) 18:4: You are to give them the first fruits of your grain, new wine and olive oil, and the first wool from the shearing of your sheep.
2) Commentary of Rabbi Yaakov ben Asher on the Torah - The sheep were not actually sacrificed, only consecrated to G-d. We see later that Noah, who was allowed to eat animals, gave his offerings upon an altar and clearly sacrificed them. See Genesis 8:20: And Noah built an altar to the Lord, and he took of all the clean animals and of all the clean fowl and brought up burnt offerings on the altar. In other discussions of sacrifices in the Torah, they almost always mention an altar or method of sacrifice. However, by Hevel (Abel) the Torah tells us only that he “brought them.”
I find this explanation difficult because the Talmud in Tractate Zevachim 116a describes Hevel (Abel’s) offering as an actual sacrifice.
3) Many, many commentaries explain that the sheep were actually slaughtered. The Talmud, Sanhedrin 59b cites Bereshis (Genesis) 1:29-30 as the source of Adam’s prohibition against eating meat:
And God said, "Behold, I have given you every seed bearing herb, which is upon the surface of the entire earth, and every tree that has seed bearing fruit; it will be yours for food. And to all the beasts of the earth and to all the fowl of the heavens, and to everything that moves upon the earth, in which there is a living spirit, every green herb to eat," and it was so.
Tosafos (a compilation of medieval critical commentaries on the Talmud) explains that this was specifically a prohibition against killing animals for food. Adam was permitted, however, to eat of an animal that died on its own.
Rambam (Hilchos Melachim 9:1) holds, that Adam was completely prohibited from eating any meat.
The Aruch LaNer (Rabbi Yaakov Ettlinger, 1798 – 1871) explains that Tosafos holds Adam was permitted to kill and use animals for other purposes. Note that the Torah doesn’t actually prohibit eating meat in Genesis 1:29 to 30, it only states what is permitted to eat – vegetation. The concern of the Torah appears to be entirely dietary.
Admittedly, Tosafos’s explanation is difficult to understand, because it does not fit in well with the plain language of the Talmud or the Torah. However, it certainly explains why Hevel (Abel) was able (no pun intended) to give an offering of a sheep.
According to Rambam, however, who holds that Adam was not at all allowed to eat meat, Hevel (Abel’s) offering is difficult to explain. Apparently, the Rambam agrees that Adam was allowed to kill animals for other needs. However, if Adam was not allowed to eat animals, then he cannot have been permitted to bring them as a sacrifice. This is because there is a general rule about sacrifices: One is only allowed to bring as an offering that which he is permitted to eat.
The Kli Chemdah (Rabbi Meir Dan Plotzky) points out that this rule only applies to things that are actually prohibited from being eaten. To Adam, Meat was never actually prohibited. Rather, the Torah only told Adam what he was permitted to eat: vegetation. There was not actually a prohibition placed upon meat.
Many later Torah scholars bring proofs that this rule about sacrifices only applies to Jews, however, and not Noahides. Therefore, there would be no problem to say that Hevel (Abel) slaughtered the animals as a sacrifice.
Incidentally, the Talmud in Tractate Avodah Zarah 8a demonstrated that Adam himself brought offerings.
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