This is what the Bible says:
Abrahamic covenant and land covenant applies only to Isaac and his seed.
Genesis 17:19 (KJV) 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.
Genesis 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.
Genesis 17: 21 But my covenant will I establish with Isaac, which Sarah shall bear unto thee at this set time in the next year.
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The land which I gave Abraham and Isaac
Genesis 35:11-12 And YHWH said unto him, “I am God Almighty: be fruitful and multiply; a nation and a company of nations shall be of thee, and kings shall come out of thy loins; and the land which I gave Abraham and Isaac, to thee I will give it, and to thy seed after thee will I give the land.”
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The Land as an everlasting possession
Genesis 48:3-4 And Jacob said unto Joseph, “God Almighty appeared unto me at Luz in the land of Canaan, and blessed me, and said unto me, ‘Behold, I will make thee fruitful, and multiply thee, and I will make of thee a multitude of people; and will give this land to thy seed after thee for an everlasting possession.’”
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Israel’s land not to be sold or exchanged
Ezekiel 36:24 For I will take you from among the heathen, and gather you out of all countries, and will bring you into your own land.
Ezekiel 48:14 And they shall not sell of it, neither exchange, nor alienate the firstfruits of the land: for it is holy unto YHWH.
Ezekiel 48:29 This is the land which ye shall divide by lot unto the tribes of Israel for inheritance, and these are their portions, saith YHWH God.
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Isaac and his seed is the heir, not Ishmael
Galatians 4:22 For it is written, that Abraham had two sons, the one by a bondmaid, the other by a freewoman.
Galatians 4:23 But he who was of the bondwoman was born after the flesh; but he of the freewoman was by promise.
Galatians 4:24 Which things are an allegory: for these are the two covenants; the one from the mount Sinai, which gendereth to bondage, which is Agar.
Galatians 4:25 For this Agar is Mount Sinai in Arabia, and answereth to Jerusalem which now is, and is in bondage with her children.
Galatians 4:26 But Jerusalem which is above is free, which is the mother of us all.
Galatians 4:27 For it is written, “Rejoice, thou barren that bearest not; break forth and cry, thou that travailest not: for the desolate hath many more children than she which hath an husband.”
Galatians 4:28 Now we, brethren, as Isaac was, are the children of promise.
Galatians 4:29 But as then he that was born after the flesh persecuted him that was born after the Spirit, even so it is now.
Galatians 4:30 Nevertheless what saith the scripture? Cast out the bondwoman and her son: for the son of the bondwoman shall not be heir with the son of the freewoman.
Galatians 4:31 So then, brethren, we are not children of the bondwoman, but of the free.