Then just the simple question: Who is the barren woman?
Why does that negate the plan from the beginning of the world?
That is not so, today, in the age of grace. We are ALL on the same, level playing ground. There is neither Jew nor Gentile right now. We approach God individually, not THROUGH a nation.
BTW: re-read Matthew, Chapters 10 and 15. Clearly, He states He was NOT sent to anyone but the LOST SHEEP OF THE HOUSE OF ISRAEL. There's a reason for that, too. Rightly dividing God's word of truth would show you.