Genesis 15:1-6; 21:1-3
Chapter 15
Abram’s Covenant with the Lord
After this, the word of the Lord came to Abram in a vision: “Do not be afraid, Abram, I am your shield; your reward will be very great!”Abram said:
“My Lord God, where are your promises? I am still childless, and all I have will go to Eliezer of Damascus.
You have given me no children, so a slave of mine will be my heir.”
Then the word of the Lord was spoken to him again:
“Eliezer will not be your heir, but a child born of you (your own flesh and blood) will be your heir.”
Then the Lord brought him outside and said to him: “Look up at the sky and count the stars if you can. Your descendants will be like that.”
Abram believed the Lord, who, because of this, considered him a righteous man.
Chapter 21
The Birth of Isaac
The Lord was kind to Sarah as he had said and fulfilled his promise to her.
Sarah became pregnant and bore a son to Abraham in his old age, at the very time the Lord had promised.
Abraham named the son that Sarah bore him Isaac
Commentaries
Abram’s Covenant with the Lord.
God retakes the initiative in this story with Abram, which began in chapter 12. Once more, a promise: “Do not be afraid, I am your shield” (1). For the first time, Abram responds to the Lord: without heirs, gifts are of little use (2-3). Then follows the ratification of the promise, which will be infinitely prolonged thanks to an heir born from the very entrails of the patriarch (4). This promise has not yet been fulfilled, but the Word of the Lord is committed to it. Verses 9f describe how a covenant or alliance was sealed. The novelty of this covenant between the Lord and Abram, emphasizing its absolute gratuitousness, is that God is one of the covenanters or co-participants. In standard practice, the divinity or divinities served as witnesses of the covenant; here, God is both witness and covenanter, providing even greater assurance of fulfillment.
Some argue that, given this condition, one cannot speak strictly of a covenant, but instead of God’s firm promise to Abram. Regardless of the case, what stands out in the story is the deep and intimate union of God with the people, whose bonds are definitively strengthened by a covenant whose immediate effect is to establish paternity on the part of the principal contracting party—in this case, God himself— the filiation of the secondary contracting party, in this case Abram, and the fraternity of all among themselves. These types of bonds, created by alliances, prove to be much stronger than the blood bonds themselves.
Verses 13f serve not primarily as predictions of what will happen to the people of Egypt but rather as confirmations of what has occurred. Verses 18b-21 detail the geography of the promised land, the entirety of which could never be fully realized.
The Birth of Isaac.
This text consists of two distinct parts. The first (1-8) discusses the fulfillment of the promise (17:15f) regarding the birth of Isaac and features the words of Sarah (6f), the earliest recorded words in the entire history of the matriarchs. The redactors recount the tradition that it is the father’s role to name the children (3), the law mandating circumcision on the eighth day (4), and the custom of holding a feast on the day of the infant’s weaning (8). However, the key message is found in the second part (9-21), where the fates of Ishmael and Isaac are established. Ishmael will also share in the blessing and the promise of many descendants that will carry on after Abraham through Isaac (13b.18).
This story should not be seen as a narration of the fate of Isaac—the Hebrew people—and Ishmael—the Ishmaelites or Arabs. Instead, it confirms the relationship between the two ethnic groups, whose origins are lost in time. The story serves as a literary resource to establish the moment when the enduring antagonism between these two groups begins.