God in the Bible asserts the blessing of Ishmael’s descendants in more than one verse as shown:
Genesis 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; twelve princes shall he beget, and I will make him a great nation.
Genesis 17:7 And I will establish my covenant between me and you and your seed after you throughout their generations for an everlasting covenant, to be a God unto you and to your seed after you.
Genesis 21:13 And also of the son of the handmaid will I make a nation, because he is your seed.
Genesis 21:17 And God heard the voice of the lad. And the angel of God called to Hagar out of heaven, and said unto her, What aileth you , Hagar? Fear not. For God hath heard the voice of the lad where he is. Gen 21:18 Arise, lift up the lad, and hold him in your hand. For I will make him a great nation.
What does a blessing of Ishmael mean?
As we see here, God in the Bible is talking about Ishmael being blessed, and that he will have a great nation. According to the Bible, a blessing means prophecy among his descendants. For example if we looked at Genesis 27 at the story when Jacob took the blessing from Esau and its result, we would realize prophets were raised from Esau’s descendants, but many prophets were raised from Isaac’s seed. And Prophet Muhammad ﷺ was raised from Ishmael’s descendants who are the brothers of Israel as the Bible tells in Deuteronomy 18:18.
Someone might say that this prophecy was fulfilled in the verse which says that Ishmael shall have 12 sons as in Genesis 25:13-14. Actually if the blessing was just regarding descendants, then actually Esau had two great nations as well, not only the Edomites as mentioned in the Bible, but also the Romans as mentioned in the Talmud, and the greatness of the Roman empire is well known to everybody. So it’s clear here that the blessing is not related to a fruitful nation, otherwise we would have seen Esau blessed as well, but a blessing rather means that a great prophet shall come from Ishmael’s descendants.
Isn’t the covenant of God established with Isaac only?
It might be said that the covenant is with Isaac only as the Bible says:
Genesis 17:21 But my covenant will I establish with Isaac, whom Sarah shall bear unto you at this set time in the next year.
Matthew 21:43 therefore say I unto you, The kingdom of God shall be taken away from you, and shall be given to a nation bringing forth the fruits thereof.
Calling Ishmael as a fruitful, that he shall have a great nation is very clear in praising him, otherwise, if God knew that a false prophet came from his descendants where a great nation followed him, why did He describe this nation to be great?
Also the nation Jesus told here doesn’t mean the Christian nation, God said that the sign of the covenant between him and the descendants of Abraham shall be the circumcision, which should be one of the fruits of the kingdom of God:
Geesisn 17:10 This is my covenant, which ye shall keep, between me and you and thy seed after thee: every male among you shall be circumcised… 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. 14 And the uncircumcised male who is not circumcised in the flesh of his foreskin, that soul shall be cut off from his people; he hath broken my covenant.
So it clearly tells that the sign of this covenant is circumcision, this covenant is everlasting and that the one who don’t circumcise breaks God’s covenant, which Muslims already do while according to Christians , Paul cancelled circumcision. Muslims are the real followers of Abraham. The Bible says:
Genesis 12:3 and I will bless them that bless you, and him that curseth you will I curse: and in you shall all the families of the earth be blessed.
Muslims bless Abraham at least 5 times a day in their prayer. At the end of every prayer, a Muslim must say:
“O Allah! send your Salat (Blessings, Graces, Honors and Mercy) on Muhammad and the family of Muhammad as You sent Your Salat on Abraham and the family of Abraham. O Allah! Send Your Blessings on Muhammad and the family of Muhammad as You sent Your Blessings on Abraham and the family of Abraham. You are Praiseworthy, Most Gracious.”
So if Muslims bless Abraham, the Bible says that God blesses who bless him, how come the followers of a false prophet be blessed by God?