Actually, we were talking about Christ and His promises, one of which was to build up a people from all the nations. It’s called the Church, and it is composed of both Jews and gentiles, the spiritual children of Abraham. This was foretold by God in the Old Testament when He promised to Abraham that he would be a father of many nations (Gen. 17:4; Rom. 4:16-18). “Therefore it is of faith that it might be according to grace, so that the promise might be sure to all the seed, not only to those who are of the law, but also to those who are of the faith of Abraham, who is the father of us all.” This is the Church.
Of course the Jews of Jesus day did not appreciate the fact that Abraham was also the father of gentiles according to the promise. They boasted in their ethnicity. "Abraham is our father" (John 8:39). But Abraham believed while he was still uncircumcised, indicating the true nature of righteous and the universal aspect of God’s holy people.
But Ryrie, et al say that this was unknown in the Old Testament, not simply concealed. I don’t think I’m the one confusing anything since I do not subscribe to The System®.
No. It is called Israel. Please see my post immedately above this one.