Genesis 15:10

“And he took unto him all these, etc.] The heifer, goat, ram, turtle, and young pigeon, not to himself, but to the Lord, as he was bid, and offered them before him, as the above Targums paraphrase it; or however he took them for his use, and set them before him, and did with them as he directed him: and divided them in the midst; that is, the three animals, the heifer, goat, and ram; he did not take off their several limbs, and cut them up in small parts, but cut them in halves; and laid each piece one against another; one half against the other, the left side against the right, shoulder against shoulder, and leg against leg, so that they might seem to join, or might be easily joined together…”

“- The Faith of Abram 1. דבר dābār, “a word, a thing;” the word being the sign of the thing. 2. אדני 'ǎdonāy, “Adonai, the Lord;” related: “bring down, lay down.” This is the name usually read in place of Yahweh; but when, as in the present case, יהוה yehovâh and אדני 'ǎdonāy are in apposition, אלהים 'ĕlohı̂ym is read instead of the former. The Jews from a feeling of reverence avoided the utterance of this sacred name except on the most solemn occasions. This is said to have arisen from a stringent interpretation of Leviticus 24:16. According to some, this name was pronounced only once a year by the high priest, on the day of atonement, in the Holy of Holies, and according to others…”

“15:10 Obeying God’s instructions, Abram gathered three herd animals for the ceremony and cut them in half. Cutting the animals symbolized the oath, indicating that the covenant maker staked his own life on his word (Jer 34:18).”