Gen 17:10 This is my covenant, which ye shall keep, between me and you and thy seed after thee; Every man child among you shall be circumcised.
The covenant with the physical lineage of Abraham through Isaac was circumcision. The New Covenant was by faith in Jesus. Children of faith are cleansed by the blood of Jesus and the indwelling of the Holy Ghost. Baptism is the sign of the new covenant.
Gen 17:11 And ye shall circumcise the flesh of your foreskin; and it shall be a token of the covenant betwixt me and you.
Gen 17:12 And he that is eight days old shall be circumcised among you, every man child in your generations, he that is born in the house, or bought with money of any stranger, which is not of thy seed.
Science has confirmed that by the 8th day, the baby has better protection to prevent bleeding.
Gen 17:13 He that is born in thy house, and he that is bought with thy money, must needs be circumcised: and my covenant shall be in your flesh for an everlasting covenant.
Gen 17:14 And the uncircumcised man child whose flesh of his foreskin is not circumcised, that soul shall be cut off from his people; he hath broken my covenant.
The circumcision rite and the law would characterize the Covenant with Moses. The everlasting covenant through Abraham required the outward circumcision and the inward obedience by faith.
Gen 17:15 And God said unto Abraham, As for Sarai thy wife, thou shalt not call her name Sarai, but Sarah shall her name be.
Sarai meant, my princess, a princess of one family. Sarah meant princess of a multitude.
Gen 17:16 And I will bless her, and give thee a son also of her: yea, I will bless her, and she shall be a mother of nations; kings of people shall be of her.
Sarah had to be part of the blessing, for the heir would be born through her, a miracle at her age and being barren.
Gen 17:17 Then Abraham fell upon his face, and laughed, and said in his heart, Shall a child be born unto him that is an hundred years old? and shall Sarah, that is ninety years old, bear?
That would be funny, except God said it. We must be careful to respect God's word and commands. It was joyful laughter, the kind that follows good news and blessings.
Gen 17:18 And Abraham said unto God, O that Ishmael might live before thee!
What about Ishmael? He was concerned about him.
Gen 17:19 And God said, Sarah thy wife shall bear thee a son indeed; and thou shalt call his name Isaac: and I will establish my covenant with him for an everlasting covenant, and with his seed after him.
Sarah is to be the mother, not a slave. And the covenant will be established through your son, Isaac, meaning laughter.
Gen 17:20 And as for Ishmael, I have heard thee: Behold, I have blessed him, and will make him fruitful, and will multiply him exceedingly; twelve princes shall he beget, and I will make him a great nation.
God was merciful to Ishmael too. He is concerned even more so about people than we are. Twelve princes and he shall be a great nation. Jacob would have 12 princes too, and from his lineage the Prince of peace, the Lord of Lords.
Gen 17:21 But my covenant will I establish with Isaac, which Sarah shall bear unto thee at this set time in the next year.
The time of the birth is announced; through Sarah and this would be the establishing of the Abrahamic Covenant.
Gen 17:22 And he left off talking with him, and God went up from Abraham.
God went up, or the angel speaking for God. Some think it was Jesus who appeared before the incarnation.
Gen 17:23 And Abraham took Ishmael his son, and all that were born in his house, and all that were bought with his money, every male among the men of Abraham's house; and circumcised the flesh of their foreskin in the selfsame day, as God had said unto him.
Gen 17:24 And Abraham was ninety years old and nine, when he was circumcised in the flesh of his foreskin.
Gen 17:25 And Ishmael his son was thirteen years old, when he was circumcised in the flesh of his foreskin.
Gen 17:26 In the selfsame day was Abraham circumcised, and Ishmael his son.
Gen 17:27 And all the men of his house, born in the house, and bought with money of the stranger, were circumcised with him.
All obeyed the covenant through circumcision. The covenant was entered by a work of the flesh, through obedience and faith in the promises. The law of Moses would continue with this sign, adding to it obedience to the laws. Jesus made a new covenant through his cut and torn flesh for us. It was no longer required of us to be circumcised or to do the works of the law, but it was through faith in the work of Jesus that we are saved, by faith we receive grace. We follow in baptism and the heart is circumcised. God works in us to do his good pleasure.
Requirements of Abrahamic Covenant Keepers
1. God expects us to be honest and guileless towards him, in our willingness to keep the terms of his covenant with us. We must be blameless, not hypocritical and two-faced (17:1).
2. We must respond to God's covenant towards us by taking on the sign of the covenant -- for the Jew, circumcision, for the Christian, baptism (17:10).
3. We, like Abraham, should be immediately obedient to do what God tells us to do, and not put it off, no matter how difficult. One sign of Abraham's faith is his immediate obedience to confirm God's covenant with him through circumcision (17:23).