Who according to you mean 'Gentiles'.
In OT, the word 'Guyim' meant nations.
If one reads OT, Abraham was prophesied on to be the father of many nations. The prophecy was to do with the multiplication of his seed. The prophecy was made when he was childless. He believed in YHWH's prophecy when he was without the child of promise. This was accounted to him for righteousness.
Most Christians don't know that they are from the mixed seed of Abraham because the northern kingdom of Israel was dispersed after their Assyrian captivity - save alone some settled in Samaria.
Heb 11:
11 By belief also, Sarah herself was enabled to conceive seed, and she bore a child when she was past the normal age, because she deemed Him trustworthy who had promised.
12 And so from one, and him as good as dead, were born
as numerous as the stars of the heaven, as countless as the sand which is by the seashore. Gen. 15:5;
22:17.