fine sawdust of carpenters, lime, crushed potsherd, and a brick or the lid of an earthenware barrel that one crushed? The verse states: “And cover it,” i.e., with any substance. One might have thought that I will include even thick manure, and thick sand, filings of metal vessels, a brick or a lid that one did not crush, flour, bran, and coarse bran. Therefore, the verse states: “And cover it with earth,” indicating that not all substances may be used to cover the blood.

The Gemara asks: And what did you see that led you to include these substances and to exclude those? The Gemara responds: After noting that the verse included certain substances with the term: “And cover it,” and excluded others with the term: “With earth,” I include these substances, e.g., fine sand, which are a type of earth in which plants grow, and I exclude those substances, e.g., thick sand, which are not a type of earth, as plants do not grow in them.

The Gemara asks: Why must the verse be interpreted in this manner? Say that the term: “And cover it,” is a generalization, and the term: “With earth,” is a detail. Consequently, the verse constitutes a generalization and a detail, and according to the corresponding hermeneutical principle, the generalization includes only what is mentioned explicitly in the detail. Therefore, only earth may be used to cover the blood, while any other substance, even substances in which plants grow, may not be used.

Rav Mari said in response: One should not suggest such an interpretation because the term “and cover it” is a generalization that requires a detail to clarify its nature, and any generalization that requires a detail to clarify its nature is not interpreted by the hermeneutical principle of a generalization and a detail. It is necessary for the verse to state that the blood must be covered with earth in order to clarify that the mitzva of covering the blood is such that the blood must be covered with a substance that will absorb the blood, and that it does not suffice to place a vessel over it.

§ Rav Naḥman bar Rav Ḥisda taught: One may not cover the blood of an undomesticated animal or a bird except with a substance in which seed is sown and sprouts. Rava said: This is an absurdity [burkha], as the mishna and baraita both teach that one may use substances in which seeds do not sprout.

Rav Naḥman bar Yitzḥak said to Rava: What is the absurdity of his statement? I said this statement to Rav Naḥman bar Rav Ḥisda and I said it to him from this baraita: If one is traveling in the desert, where the earth is not arable, and wishes to slaughter an undomesticated animal or a bird, but he does not have dirt with which to cover the blood, he may grind a gold dinar into powder and cover the blood with it. If one is traveling on a ship and wants to slaughter an undomesticated animal or a bird but he does not have earth with which to cover the blood, he may burn his garment and cover the blood with the ashes. It is evident from the first clause of the baraita that desert sand, which does not allow for the sprouting of seeds, may not be used to cover the blood of an undomesticated animal or a bird.

The Gemara analyzes the baraita: Granted, it is understood that one may burn his garment and cover the blood with the ashes, since we found a source for the fact that ashes are called earth [afar], as the Gemara will soon prove; accordingly, the use of ashes is in accordance with the verse: “And cover it with earth.” But with regard to a gold dinar, from where do we derive that one may grind it into powder and use it to cover the blood? Rabbi Zeira said: The verse states: “And it has dust of [afrot] gold” (Job 28:6), indicating that gold is referred to as dust.

The Gemara cites a related baraita in which the Sages taught: One may not cover the blood of an undomesticated animal or a bird except with earth; this is the statement of Beit Shammai. And Beit Hillel say: We find that ashes are called dust [afar], as it is stated with regard to the red heifer: “And for the impure they shall take from the ashes [me’afar] of the burning of the purification from sin” (Numbers 19:17). And Beit Shammai respond: Ashes are called dust of the burning [afar sereifa], but they are not called ordinary dust [afar].

The Gemara notes: It is taught that the Sages added the following to the list of substances in the mishna with which one may cover the blood: Coal dust, stibium [keḥol], and shavings from chiseling. And some say they included even arsenic [zarnikh].

§ The Gemara cites aggadic accounts relating to the mitzva of covering the blood: Rava says: As reward for that which our Patriarch Abraham said: “And I am but dust [afar] and ashes” (Genesis 18:27), his children merited two mitzvot: The ashes of the red heifer (see Numbers, chapter 19) and the dust of the sota, i.e., dirt taken from the ground of the Tabernacle that is mixed into the water that examines whether or not a woman committed adultery (see Numbers 5:17).

The Gemara challenges: But let Rava also consider the earth used in the mitzva of covering the blood. The Gemara responds: There, the earth does serve as an accessory to the mitzva of covering the blood, but there is no benefit imparted by it. It occurs after the animal has been slaughtered and does not itself render the meat fit for consumption. By contrast, the ashes of the red heifer and the dust of the sota provide benefit, as the former purifies one who became ritually impure and the latter leads to peace between husband and wife when drinking the water proves that she did not commit adultery.

And Rava says: As reward for that which our Patriarch Abraham said to the king of Sodom: