Ted's Response:

In God's covenant with Abram (before he was named Abraham), a certain expanse of land was promised to his descendants:

On that day the LORD made a covenant with Abram and said, "To your descendants I give this land, from the river of Egypt to the great river, the Euphrates—the land of the Kenites, Kenizzites, Kadmonites, Hittites, Perizzites, Rephaites, Amorites, Canaanites, Girgashites and Jebusites." (Genesis 15:18-21)

The promises were spoken to Abraham and to his seed. The Scripture does not say "and to seeds," meaning many people, but "and to your seed," meaning one person, who is Christ. (Galatians 3:16)

In the chapters of Ezekiel 35—39 are described the attacks upon Israel near the end of the 70th Week, as well as how the Lord (Jesus, the Messiah) will return to save the Israelites (see When do the events of Ezekiel chapters 35-39 take place? and When does the Gog/Magog battle, described in Ezekiel chapters 38 and 39, occur?).

Following that, Ezekiel 40—46 describes the millennial Temple and Holy Hountain, the land on which it will stand, and what will go on within that Temple. Then, Ezekiel wrote,

This is what the Sovereign LORD says: "These are the boundaries by which you are to divide the land for an inheritance among the twelve tribes of Israel, with two portions for Joseph. You are to divide it equally among them. Because I swore with uplifted hand to give it to your forefathers, this land will become your inheritance." (Ezekiel 47:13,14)

Before Abraham even had any children, God had told Abraham that He would give him a son by his wife, Sarah (Genesis 17:15,16). This son would be Isaac. However, since she was barren, Sarah wrongly "took matters into her own hands" and gave her handmaiden slave, Hagar, to Abraham to bear him a son. Essentially, Abraham took a supernatural promise and "downgraded" it into a natural promise, which never is a good idea when God is involved, since it demonstrates a lack of faith.

Subsequently, God chose to give the inheritance, which He had promised Abraham (Abram), to Isaac, Abraham’s second-born, rather than to Ishmael, his first-born (Genesis 17:18-21). This is because Isaac was the son God had promised to Abraham. Also, Ishmael was the son of Hagar, a slave woman; but Isaac was the son of Sarah, a free woman (Galatians 4:22-28).

Interestingly, after Abraham, demonstrating great humility and sacrifice, had been willing to give his son Isaac back to God, the Lord told Abraham that He would bless him greatly because he had not withheld his "only son" from God (Genesis 22:15-17). God called Isaac Abraham's "only son," even though Abraham had an elder son, Ishmael. This was because Isaac was recognized, by God, as Abraham's only legitimate son—the son of the original promise.

Hebraic people, among the twelve tribes of Israel, are descendants of Isaac, through Isaac's son Jacob (also called "Israel"). Jesus spoke of a great feast to come in the kingdom of heaven, at which Abraham, Isaac, and Jacob would be in attendance (Matthew 8:11). Ishmael is not mentioned.

Descendants of Jacob (Israel) are God's chosen people (Isaiah 65:9). Even David, a great king held in very high esteem by Jews, Christians, and Muslims alike, stated this as part of a "Psalm of Thanks":

O descendants of Abraham his servant, O sons of Jacob, his chosen ones. He is the LORD our God; his judgments are in all the earth. He remembers his covenant forever, the word he commanded, for a thousand generations, the covenant he made with Abraham, the oath he swore to Isaac. He confirmed it to Jacob as a decree, to Israel as an everlasting covenant: "To you I will give the land of Canaan as the portion you will inherit." (Psalm 105:6-11)

As written by Moses, God said this to the Israelites:

Acknowledge and take to heart this day that the LORD is God in heaven above and on the earth below. There is no other. Keep his decrees and commands, which I am giving you today, so that it may go well with you and your children after you and that you may live long in the land the LORD your God gives you for all time. (Deuteronomy 4:39,40)