I think you have misunderstood this.
He was the first Jew and the father to the 12,13 or 14 tribes (depending where in the bible you are).
Genesis 17
1 When Abram was ninety-nine years old, the Lord appeared to him and said, “I am God Almighty; walk before me faithfully and be blameless.
2 Then I will make my covenant between me and you and will greatly increase your numbers.”
10 This is my covenant with you and your descendants after you, the covenant you are to keep: Every male among you shall be circumcised.
11 You are to undergo circumcision, and it will be the sign of the covenant between me and you.
14 Any uncircumcised male, who has not been circumcised in the flesh, will be cut off from his people; he has broken my covenant.”
15 God also said to Abraham, “As for Sarai your wife, you are no longer to call her Sarai; her name will be Sarah. 16 I will bless her and will surely give you a son by her. I will bless her so that she will be the mother of nations; kings of peoples will come from her.”
20 And as for Ishmael, I have heard you: I will surely bless him; I will make him fruitful and will greatly increase his numbers.
He will be the father of twelve rulers, and I will make him into a great nation.
26 Abraham and his son Ishmael were both circumcised on that very day.
27
And every male in Abraham’s household, including those born in his household or bought from a foreigner, was circumcised with him.
Revelation 7
5 From the tribe of Judah 12,000 were sealed,
from the tribe of Reuben 12,000,
from the tribe of Gad 12,000,
6 from the tribe of Asher 12,000,
from the tribe of Naphtali 12,000,
from the tribe of Manasseh 12,000,
7 from the tribe of Simeon 12,000,
from the tribe of Levi 12,000,
from the tribe of Issachar 12,000,
8 from the tribe of Zebulun 12,000,
from the tribe of Joseph 12,000,
from the tribe of Benjamin 12,000.