Now the Lord had said to Abram, Get out of your country, from your kindred and from your father's house, to a land that I wil show you. And I will make you a great nation, and I will bless you and make your name great; and you shall be a blessing. I will bless those who bless you, and I will curse those who curse you; and in you all the families of the earth shall be blessed. So Abram departed as the Lord had spoken to him, and Lot went with him. And Abram was seventy-five years old when he departed from Haran. (Genesis 12:1-4)

Now Sarai, Abram's wife, had borne him no children. And she had an Egyptian maidservant whose name was Hagar. So Sarai said to Abram, See now, the Lord has restrained me from having children. Please go in to my maid; perhaps I shall obtain children by her. And Abram heeded the voice of Sarai. Then Sarai, Abram's wife, took Hagar her maid, the Egyptian, and gave her to her husband Abram to be his wife, after Abram had dwelt ten years in the land of Canaan. So Hagar bore Abram a son; and Abram named his son, whom Hagar bore, Ishmael. Abram was eighty-six years old when Hagar bore Ishmael to Abram. (Genesis 15:1-3, 15, 16)

Praise be to God who has given to me when I am old Ishmael and Isaac. (Surah No. 14 Ibrahim:39)

When Abram was ninety-nine years old, the Lord appeared to Abram and said to him, I am Almighty God; walk before me and be blameless. Then God said to Abraham, As for Sarai your wife, you shall not call her name Sarai, but Sarah shall be her name. And I will bless her and also give you a son by her; then I will bless her and she shall be a mother of nations; kings of peoples shall be from her. Then Abraham fell on his face and laughed, and said in his heart, Shall a child be born to a man who is one hundred years old? And shall Sarah who is ninety years old, bear a child? And Abraham said to God, Oh, that Ishmael might live before you.

Then God said, Sarah your wife shall bear you a son, and you shall call his name Isaac; I will establish my covenant with him for an everlasting covenant, and with his seed after him.

And as for Ishmael, I have heard you. Behold, I have blessed him, and will make him fruitful, and will multiply him exceedingly. He shall begat twelve princes, and I will make him a great nation.

But my covenant I will establish with Isaac, whom Sarah shall bear to you at this set time next year. Then He finished talking with him and God went up from Abraham. (Genesis 17:1, 15-22)

The blessing of God promised to Ishmael and the covenant of God established with Isaac are not mentioned in the Koran.

Then the Lord appeared to him by the terebinth trees of Mamre, as he was sitting in the tent door in the heat of the day. So he lifted his eyes and looked, and behold, three men were standing by him; and when he saw them, he ran from the tent door to meet them, and bowed himself to the ground, and said, My Lord, if I have now found favor in your sight, do not pass on by your servant. Please let a little water be brought , wash your feet, and rest yourselves under the tree. And I will bring a morsel of bread, that you may refresh your hearts. After that, you may pass by, inasmuch as you have come to your servant. And they said, Do as you have said. So Abraham hastened into the tent to Sarah and said, Quickly, make ready three measures of fine meal; knead it and make cakes. And Abraham ran to the herd, took a tender and good calf, gave it to a young man, and he hastened to prepare it. So he took butter and milk and the calf which he had prepared, and set it before them; and he stood by them under the tree as they ate. Then they said to him, Where is Sarah your wife? And he said, Here, in the tent, And He said, I will certainly return to you according to the time of life, and behold, Sarah your wife shall have a son. And Sarah was listening in the tent door which was behind him. Now Abraham and Sarah were old, well advanced in age; and Sarah had passed the age of childbearing. Therefore Sarah laughed within herself, saying, After I have grown old, shall I have pleasure, my lord being old also? And the Lord said to Abraham, Why did Sarah laugh, saying, Shall I surely bear a child since I am old? Is anything too hard for the Lord? At the appointed time I will return to you, according to the time of life, and Sarah shall have a son. (Genesis 18:1-14)

And indeed our messengers came to Abraham with good news. They said, Peace! He said, Peace! and he did not delay bringing the roasted calf. And when he saw their hands reached not to it, he mistrusted them and feared them. They said, Don't be afraid, verily we are sent to Lot's people. And his wife standing by laughed and we gave her good news of Isaac and from beyond Isaac, Jacob. She said, Oh, woe is me, shall I bear a child and I am an old woman and this my husband is an old man? Truly, this is a wonderful thing. They said, Do you wonder at the command of God? The mercy of God and His blessings on you O people of the house. Truly He is praised, glorious. (Surah No. 11 Hud:69-73)

And the Lord visited Sarah as He had said, and the Lord did for Sarah as He had spoken. For Sarah conceived and bore Abraham a son in his old age, at the set time of which God had spoken to him. And Abraham called the name of his son who was born to him--whom Sarah bore to him--Isaac. Now Abraham was one hundred years old when his son Isaac was born to him. (Genesis 21:1-3, 5)

Praise be to God who has given to me when I am old Ishmael and Isaac. (Surah No. 14 Ibrahim:39)

Abraham made a great feast on the same day that Isaac was weaned. And Sarah saw the son of Hagar the Egyptian, whom she had born to Abraham, scoffing. Therefore she said to Abraham, Cast out this bondwoman and her son; for the son of this bondwoman shall not be heir with my son, namely with Isaac. And this matter was very displeasing in Abraham's sight because of his son. But God said to Abraham, Do not let it be displeasing in your sight because of the lad or because of your bondwoman. Whatever Sarah has said to you, listen to her voice; for in Isaac your seed shall be called. Yet I will also make a nation of the son of the bondwoman because he is your seed. So Abraham rose early in the morning, and took bread and a skin of water; and putting it on her shoulder, he gave it and the boy to Hagar, and sent her away. Then she departed and wandered in the wilderness of Beersheba. And the water in the skin was used up, and she placed the boy under one of the shrubs. So she sat opposite him, and lifted up her voice and wept. And God heard the voice of the lad. Then the angel of God called to Hagar out of heaven, and said to her, What ails you, Hagar? Fear not, for God has heard the voice of the lad where he is. Arise, lift up the lad and hold him with your hand, for I will make him a great nation. And God opened her eyes, and she saw a well of water. Then she went and filled the skin with water, and gave the lad a drink. So God was with the lad; and he grew and dwelt in the wilderness of Paran, and became an archer. (Genesis 21:8-15, 17-20)

And as for Ishmael, I have heard you. Behold, I have blessed him, and will make him fruitful, and will multiply him exceedingly. He shall beget twelve princes, and I will make him a great nation. (Genesis 17:20)

Now this is the genealogy of Ishmael, Abraham's son, whom Hagar the Egyptian, Sarah's maidservant, bore to Abraham. And these were the names of the sons of Ishmael, by their names, according to their generations: The firstborn of Ishmael, Nebajoth; then Kedar, Adbeel, Mibsam, Mishma, Dumah, Massa, Hadad, Tema, Jetur, Naphish, and Kedemah. These were the sons of Ishmael and these were their names, by their towns and their settlements, twelve princes according to their nations. (Genesis 25:12-16)

Although God did not promise a blessing to all nations through the seed of Ishmael He did completely fulfill His promises to Ishmael in that He made him fruitful, multiplied his descendants exceedingly, and made him the father of a great nation of people. The millions of Arabs in the world today are proof themselves of the fulfillment of these promises.