Komentaryo sa Genesis 15:10: Rashi, Chizkuni, Ramban & Radak

ויבתר אתם AND HE SPLIT THEM — He divided each into two portions. This verse does not lose its literal meaning although there are various Midrashic explanations of it. Since He was making a covenant with him to keep His promise to give the land as an inheritance to his children — as it is written (Genesis 15:18), “In that day the Lord made a covenant with Abram, saying …” — and as it was the custom for parties to a covenant to divide an animal and to pass between its parts, as it is said elsewhere (Jeremiah 34:19) “who passed between the parts of the calf”, so also here the smoking furnace and the flaming torch which passed between the pieces (Genesis 15:17) were representative of the Divine Shechinah which is spoken of as fire.

ויקח לו את כל אלה, “He took all these animals for Him;” our sages in Bereshit Rabbah claim that G-d showed Avram even what the measurement of a tenth of an eyfah looked like, (part of meal offerings). This is based on Bereshit Rabbah 34,14 where similar expressions are quoted as occurring here and in Leviticus 2,8: והבאת...מאלה where that meal offering is discussed.

AND HE DIVIDED THEM IN THE MIDST. This he did in order that He make the covenant with him, to pass between these parts.
He thereby alluded to Abraham that all sacrifices of cattle and fowl will be from these species since the gozeil (young pigeon) mentioned here²⁶⁴In Verse 9 above. is identical with the ben yonah (young pigeon) mentioned in the Book of Leviticus.²⁶⁵1:14. Here it is called gozeil to indicate that only the young of this specie are fit for sacrifices. Now even though all young fowl are called gozlim — as it is said, As an eagle that stirreth up her nest, hovereth over ‘gozalav’ (his young ones)²⁶⁶Deuteronomy 32:11. — Abraham understood on his own that the command of the Eternal applied to the kind which was to be selected [by the Torah, namely, young pigeons]. It may be that Abraham followed his own will in offering a young pigeon, and Scripture selected forever the specie which the patriarch had offered.
Thus did Abraham know that the sacrifices would be of these species and that all of them would be divided into parts: the Whole-offering into its pieces,²⁶⁷Leviticus 1:12. the Peace-offering into the breast, shoulder and fats,²⁶⁸Ibid., 7:30-32 and the Sin-offering and the Guilt-offering into their fats.²⁶⁹Ibid., 4:31; 7:2-5.

ואת הצפור לא בתר BUT THE BIRDS SPLIT HE NOT — Because other nations are compared to bulls, rams and goats, as it is said (Psalms 22:13) “Many bulls have encompassed me”, and it says, (Daniel 8:20) “The ram which thou sawest having two horns, they are the kings of Media and Persia” and it further says, (Daniel 8:21) “And the rough he-goat is the king of Greece” — and Israel is compared to young doves, as it is written, (Song 2:14) ‘‘O my dove that art in the clefts of the rock” — he therefore divided the animals indicating that other nations will gradually perish, ואת הצפור לא בתר but “the birds split he not”, suggesting thereby that Israel will live forever (Pirkei D'Rabbi Eliezer 28).