CHAPTER 17 Jan. 9 
Yahweh Re-Affirms the Covenant Promises
When Abram was ninety-nine years old, Yahweh appeared to Abram, and said to him, I am God Almighty. Walk before me, and be blameless. 2I will make my covenant between me and you, and will multiply you exceedingly. 3Abram fell on his face. God talked with him, saying, 4As for Me, behold, My covenant is with you. You will be the father of a multitude of nations. 5Neither will your name any more be called Abram, but your name will be Abraham; for I have made you the father of a multitude of nations. 6I will make you exceedingly fruitful, and I will make nations of you. Kings will come out of you. 7I will establish My covenant between Me and you and your seed after you throughout their generations for an everlasting covenant, to be a God to you and to your seed after you. 8I will give to you, and to your seed after you, the land in which you are travelling, all the land of Canaan, for an everlasting possession. I will be their God. 9God said to Abraham, As for you, you will keep My covenant, you and your seed after you throughout their generations. 10This is my covenant, which you shall keep, between Me and you and your seed after you. 
Circumcision As a Sign of the Covenant
Every male among you shall be circumcised. 11You shall be circumcised in the flesh of your foreskin. It will be a token of the covenant between Me and you. 12He who is eight days old will be circumcised among you, every male throughout your generations, he who is born in the house, or bought with money from any foreigner who is not of your seed: 13He who is born in your house, and he who is bought with your money, must be circumcised. My covenant will be in your flesh for an everlasting covenant. 14The uncircumcised male who is not circumcised in the flesh of his foreskin, that soul shall be cut off from his people. He has broken My covenant. 15God said to Abraham, As for Sarai your wife, you shall not call her name Sarai, but her name will be Sarah. 16I will bless her, and moreover I will give you a son by her. Yes, I will bless her, and she will be a mother of nations. Kings of peoples will come from her. 17Then Abraham fell on his face, and laughed, and said in his heart, A child shall be born to him who is one hundred years old! Sarah, who is ninety years old, shall give birth! 18Abraham said to God, Oh that Ishmael might live before you! 19God said, No, but Sarah, your wife, will bear you a son. You shall call his name Isaac. I will establish My covenant with him for an everlasting covenant for his seed after him. 20As for Ishmael, I have heard you. Behold, I have blessed him, and will make him fruitful, and will multiply him exceedingly. He will become the father of twelve princes, and I will make him a great nation. 21But My covenant I establish with Isaac, whom Sarah will bear to you at this set time next year. 22When He finished talking with him, God went up from Abraham. 23Abraham took Ishmael his son, all who were born in his house, and all who were bought with his money; every male among the men of Abraham’s house, and circumcised the flesh of their foreskin in the same day, as God had said to him. 24Abraham was ninety-nine years old, when he was circumcised in the flesh of his foreskin. 25Ishmael, his son, was thirteen years old when he was circumcised in the flesh of his foreskin. 26In the same day both Abraham and Ishmael, his son, were circumcised. 27All the men of his house, those born in the house, and those bought with money of a foreigner, were circumcised with him.

Commentary

17:5 Abram means 'high / exalted father', and can mean “he is of exalted ancestry”. Yet Abram's name was changed. He was to be the father of a new family, as 'Abraham' implied, and to sever all connection with his human ancestry and family.  The way ‘Abram’ was changed to ‘AbraHAm’ and ‘Sarah’ to ‘SarAH’ shows how God wishes to mix syllables of His Name with that of men. Jacob was changed to Isra-el, mixing God’s name with that of his father. This is indeed mutuality between God and man- and it demands so much. By baptism into the Name the same process happens to us.
17:5-11. Blessings of many children, a specific seed / son who would bring glory and blessing, and a name change... are all frequently found in records of wedding blessings. In making those promises to Abraham, in mixing the letters of His Name with that of Abram... Yahweh was entering a marriage covenant with Abraham the impotent, the childless, the humanly hopeless. And He does the very same for each of us who are baptized into that same Name and become recipients of the very same promises (Gal. 3:27-29). What was weird and so counter-instinctive was the token of the marriage covenant. Abraham was to mutilate his male generative organ as a sign that God would generate him a great seed and family. Our response to what God has promised us requires us to likewise respond in a counter-cultural and counter-instinctive way. 
17:7 The Abrahamic covenant is made personally with every member of the seed in “their generations”. The records of the renewing of the covenant to Isaac and Jacob are but indicators that this is the experience of each one of the seed. This means that the covenant love of God and the promise of personal inheritance of the land is made personally, and confirmed by the shedding of Christ's blood, to each of us. God promised Abraham that through Christ, his seed, blessing would come on people from all nations, with the result that God would be the God of Abraham's multitudinous seed: ”To be a God to... your seed...I will be their God”. The seed is Christ, and the “God” is Yahweh. In Rev. 21:3 this fundamental promise is alluded to; God Himself will be our God then; we will see Him and have a personal relationship with Him. This idea of personally being with God is a fundamental part of the Gospel preached to Abraham.
17:8 The idea of eternal life is in the Old Testament as well as the new. The promise of eternal life on earth was given to Abraham and his seed, the Lord Jesus (Gal. 3:8), but applies to all of us who are baptized into Him (Gal. 3:27-29). 
17:17 Abraham’s exaltation here is referred to in Jn. 8:56 as Abraham rejoicing to see the day of Christ.