Genesis 17

When Abram was 99, the LORD appeared and established the covenant of circumcision, renaming him Abraham and Sarai as Sarah. God promised that Sarah would bear a son named Isaac, through whom the everlasting covenant would continue. Abraham circumcised every male in his household that same day, as God had commanded.

v	King James Version	Modern English
1	And when Abram was ninety years old and nine, the LORD appeared to Abram, and said unto him, I am the Almighty God; walk before me, and be thou perfect.	When Abram was 99 years old, the LORD appeared to Abram and said to him, 'I am God Almighty; walk before me and be blameless.
2	And I will make my covenant between me and thee, and will multiply thee exceedingly.	I will make my covenant between me and You, and will multiply You greatly.'
3	And Abram fell on his face: and God talked with him, saying,	Then Abram fell on his face. God spoke with Him, saying,
4	As for me, behold, my covenant is with thee, and thou shalt be a father of many nations.	'As for me, my covenant is with you, and you shall be the father of many nations.
5	Neither shall thy name any more be called Abram, but thy name shall be Abraham; for a father of many nations have I made thee.	No longer shall your name be called Abram, but your name shall be Abraham, for I have made you the father of many nations.
6	And I will make thee exceeding fruitful, and I will make nations of thee, and kings shall come out of thee.	I will make you greatly fruitful. I will make nations of you, and kings shall come from you.
7	And I will establish my covenant between me and thee and thy seed after thee in their generations for an everlasting covenant, to be a God unto thee, and to thy seed after thee.	I will establish my covenant between me and you and your seed after you throughout their generations for an everlasting covenant, to be God to you and to your seed after you.
8	And I will give unto thee, and to thy seed after thee, the land wherein thou art a stranger, all the land of Canaan, for an everlasting possession; and I will be their God.	I will give to you and to your seed after you the land of your sojournings, all the land of Canaan, for an everlasting possession. I will be their God.'
9	And God said unto Abraham, Thou shalt keep my covenant therefore, thou, and thy seed after thee in their generations.	God said to Abraham, 'As for you, you shall keep my covenant, you and your seed after you throughout their generations.
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.	This is my covenant which you shall keep, between me and you and your seed after you: every male among you shall be circumcised.
11	And ye shall circumcise the flesh of your foreskin; and it shall be a token of the covenant betwixt me and you.	You shall be circumcised in the flesh of your foreskin. It shall be a sign of the covenant between me and you.
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.	He who is eight days old among you shall be circumcised, every male throughout your generations, whether born in your house or bought with money from any foreigner who is not of your seed.
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.	Both he who is born in your house and he who is bought with your money must be circumcised. So my covenant shall be in your flesh as an everlasting covenant.
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.	Any uncircumcised male who is not circumcised in the flesh of his foreskin shall be cut off from his people; he has broken my covenant.'
15	And God said unto Abraham, As for Sarai thy wife, thou shalt not call her name Sarai, but Sarah shall her name be.	God said to Abraham, 'As for Sarai your wife, you shall not call her name Sarai, but Sarah shall be her name.
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.	I will bless her, and moreover I will give you a son by her. I will bless her. She shall become nations; kings of peoples shall come from her.'
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?	Then Abraham fell on his face and laughed, and said in his heart, 'Shall a child be born to a man who is 100 years old? Shall Sarah, who is 90 years old, bear a child?'
18	And Abraham said unto God, O that Ishmael might live before thee!	Abraham said to God, 'Oh that Ishmael might live before you!'
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.	But God said, 'Sarah your wife shall indeed bear you a son, and you shall call his name Isaac. I will establish my covenant with him as an everlasting covenant, and with his seed after him.
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.	As for Ishmael, I have heard you. I have blessed him. I will make him fruitful and multiply him greatly. He shall father twelve princes. I will make him a great nation.
21	But my covenant will I establish with Isaac, which Sarah shall bear unto thee at this set time in the next year.	But I will establish my covenant with Isaac, whom Sarah shall bear to you at this set time next year.'
22	And he left off talking with him, and God went up from Abraham.	When he had finished talking with him, God went up from Abraham.
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.	Then Abraham took Ishmael his son and all those born in his house and all those bought with his money—every male among the men of Abraham's house—and circumcised the flesh of their foreskin that very day, as God had said to him.
24	And Abraham was ninety years old and nine, when he was circumcised in the flesh of his foreskin.	Abraham was 99 years old when he was circumcised in the flesh of his foreskin.
25	And Ishmael his son was thirteen years old, when he was circumcised in the flesh of his foreskin.	Ishmael his son was 13 years old when he was circumcised in the flesh of his foreskin.
26	In the selfsame day was Abraham circumcised, and Ishmael his son.	That very day Abraham and his son Ishmael were circumcised.
27	And all the men of his house, born in the house, and bought with money of the stranger, were circumcised with him.	All the men of his house, those born in the house and those bought with money from a foreigner, were circumcised with him.