Many Christians and Jews believe that Abraham's descendants through Ishmael are excluded from God's covenant with Abraham.
The story of Ishmael according to the Bible is as follows: Abraham married Sarah. Sarah was a barren woman and bore him no children (Genesis 16:1). True ... God made a great promise to Abraham even before any children were born to him.
"And I will make of thee a great nation, and I will bless thee, and make thy name great; and thou shalt be a blessing: And I will bless them that bless thee, and curse him that curseth thee: and in thee shall all families of the earth be blessed." (Genesis 12:2-3).
If you look at Gen. (16:15-16), Abraham was 86 years old when Ishmael was born. When Abraham was 99 years old, God made a covenant with him. God's intention to establish a covenant with Abraham is described in Gen. (17:2). The words, "And I will make my covenant with you ..." imply a future action ... long AFTER the birth of Ishmael.
A key verse is Gen. (17:18) when Abraham says, "O that Ishmael might live in your sight!". [Abraham, finding that the covenant was to be established in another branch of his family, felt solicitous for his son Ishmael, whom he considered as necessarily excluded - Adam Clarke, Bethany Bible Commentary on the Old Testament, copyright 1967].
God said "NO". "NO ... but your wife Sarah shall bear you a son, and you will name him Isaac. I will establish my covenant with him (Isaac) as an everlasting covenant for his (Isaac's) offspring after him". God delivers a remarkable prophecy which contains an answer to Abraham's prayer for Ishmael. "As for Ishmael, I have heard you; I will bless him and make him fruitful and exceeding numerous; he shall be the father of 12 princes, and I will make him a great nation. "BUT (repeat, BUT) my covenant I will establish with Isaac, whom Sarah shall bear to you at this season next year" (Genesis 17:20-21).
The scriptures teach that "My covenant I will establish with Isaac" (Genesis 17:21). Later God repeated, "In Isaac your seed shall be called" (Genesis 21:12). Isaac is the child of the promise (Genesis 17:7).
The Quran itself states that the prophetic line came through Isaac, not Ishmael: "And we bestowed on him Isaac and Jacob, and we established the prophethood and the scripture among his seed" (29:27). Neither does the Quran say that Allah established a covenant with Ishmael and his descendants.
The Muslim scholar Yusuf Ali adds the word "Abraham" and changes the meaning as follows: "we gave (Abraham) Isaac and Jacob, and ordained among his progeny prophethood and revelation." By adding in Abraham, Yusuf tries to include Muhammad in the prophetic line, but is in fact only more clearly defining Isaac's lineage. Abraham's name is not found in the arabic text of the Quran, which Muslims consider to be perfectly preserved.
Even with this addition, the prophetic line is clearly visible:
Abraham -> Isaac -> Jacob -> his seed
The name of Ishmael and his lineage is not found in this verse in any version of the Quran. Similarly, in the Bible, there are no descendants of Ishmael which were prophets.
But Ishmael is not without promise.
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