Enlarging the Covenant
Keeping Faith Alive (1-2)
There is a 14-year gap between the 16th and 17th chapters of Genesis, meaning Abraham was still waiting for fulfillment, giving glory to God, growing stronger in faith (Romans 4:20).
Before Abraham turned a century in age, Yahweh revealed Himself to Abraham as God Almighty, or "El Shaddai, the One who allows no obstacle to keep Him from fulfilling His plan."
Enlarging the Covenant (3-8)
While the fulfillment of Yahweh's covenant required no specific works from Abraham outside of faith, it did require Abraham to keep faith alive. There are always two means for keeping faith alive:
By walking before Yahweh, another way of directing Abraham to keep Yahweh at the center of His thinking and meditations.
He was to be blameless, meaning Abraham was to remain open with his life, allowing the forgiveness and mercy of God to keep him free from shame, or blameless.
This was not at any level a demand for sinlessness; this was a call to keep shame and insecurity out of his life by rendering his life disclosed before Yahweh (1-2). Abraham immediately went to his face in humble reverence, and for the fifth time, Yahweh reminded Abraham that he was in covenant relationship with Him (3).
Next, Yahweh described five new aspects to His covenant that He had made with Abraham. Up to this point in Abraham's life, he had been called Abram, but to commemorate God's enlarging scope of covenant and promise, Abram’s name was changed to Abraham. He was not just an exalted father; he was to be a father of a multitude of nations (5).
Abraham was not to be a father of one nation through Ishmael, but of a multitude of nations (4).
Abraham would become the father of many kings (6).
Abraham was receiving a covenant that would last forever and be offered to and extended to every generation after him.
Abraham's great inheritance was the inheriting of Yahweh. The key to understanding the covenant was God's promise that He would be the ultimate and genuine inheritance of Abraham and his descendants. Yahweh's key promise was that He would be God to future generations (7).
Abraham's offspring would be given to Canaan as an everlasting possession, along with God Himself. This would come to only being fulfilled in the whole world’s inheritance by Abraham's faith-children. Some argue that the word “everlasting" does not mean "enduring forever," but "enduring into the distant or foreseeable future." Either way, the promise is ultimately fulfilled (8).
Keeping the Covenant (9-14)
Yahweh, at long last, did give Abraham and his descendants a way to express their faith, a way of declaring Yahweh the Center of their lives—the act of circumcision. This rite was to be performed on every male child who was eight days old and on everyone who was a part of Abraham's household, slave or free. Circumcision became a badge of citizenship, a distinguishing mark of faith and covenant. Those who were uncircumcised or unwilling to be circumcised were to be removed from citizenship or from Abraham's family. Circumcision was not merely a rite; it was an expression of faith in Yahweh's covenant to make Abraham's offspring a great people and a great people belonging to Yahweh, a great people inheriting land (9-14).
Circumcision served five purposes:
It distinguished the seed of Abraham from all other peoples.
It perpetuated the memory of the covenant.
It provided a clear act of expressing faith in Yahweh and His promise to bless.
It reminded Abraham's offspring of their need to cultivate sexual purity. Through circumcision, the sexual act itself was dedicated to God's glory, and through sex, the marriage was dedicated to the glory of God. This is at the heart of all sexual understanding—it is an act dedicated to the glory of God.
Circumcision reminded Abraham's offspring that it was the fleshly lust around their heart affections that God was really interested in cutting away (Deuteronomy 10:16).
The imagery was obvious to Abraham—if the most private part of a man's body parts was dedicated to Yahweh, then the whole person must belong to Yahweh also.
The Sarah Promise (15-22)
Yahweh then informed Abraham by promise, for the first time, that Sarah would be blessed and have one son, and through her son would come nations and a people of kings. This was all foreshadowing Jesus and the kingdom of priests who would come from Him. Notice, she, the one who was not able to be circumcised, would become nations and a people of kings. This and the fact that Abraham was considered righteous before circumcision would not be lost on Paul, when he began to comprehend the true nature of circumcision (Romans 4:11).
To commemorate this moment and the change affecting even Sarah's body, God also changed her name from Sarai to Sarah (15-16).
For a second time, Abraham fell on his face in worship and then laughed over the impossibility of either of them having a child at their age, even with the looming modification to his sexual organ (17). Then Abraham revealed his real heart for his son Ismael, wanting him to fit favorably into God's plan and the promises made to Abraham (18).
Yahweh was emphatic—it was going to be through the son Sarah bore Abraham (whom they would name Isaac or “laughter") that this covenant to Abraham was going to be sustained to future generations (19).
God did assuage Abraham's concerns for Ishmael and reaffirmed that he would be blessed and fruitful, and He would multiply him and give him 12 sons, making Ishmael into a great nation, but the covenant to be given a special relationship with God and given the earth as a possession was going to come through the son born to Sarah.
Then came the greatest news: Sarah was going to conceive and bear a son within a year (20-21).
When Yahweh finished talking to Abraham, He went up—this means Abraham had been visited by some physical and visible manifestation of God, just as Hagar had experienced (22).
Abraham's Obedience (22-27)
The very same day Yahweh visited Abraham, he took Ishmael and circumcised him along with all the servants born in his house, as well as those he had purchased with money, not excluding himself. Abraham was 99 years old when this took place, and twice it was recorded that he obeyed Yahweh the "very day" Yahweh told him to circumcise his household. Whom Abraham circumcised was also iterated twice in this text. This was to make it clear of Abraham's immediate and complete response. Through circumcision, all the males became united—one in Yahweh, so to speak—Abraham, his son, and his servants.