Gods promises to Israel have not failed they are being fulfilled in the Church.
Galatians 3:28 neither Jew nor Greek......ye are ALL ONE in Christ Jesus.
Galatians 3:29 And if ye be Christ`s then are ye Abrahams seed,and heirs according to the promise.
Galatians 6:15 For in Christ Jesus neither circumcision availeth anything,nor uncircumcision,but a NEW CREATURE.
Galatians 6:16 And as many as walkk according to THIS RULE,peace be on them,and mercy,and upon THE ISRAEL OF GOD.
Jew and greek {i.e.gentile} are made ONE IN CHRIST and the above refers to those in Christ THE ISRAEL OF GOD.
Romans 9:8 Israel according to the flesh are not the children of God.
The same offer made to Nocodemus a JEW by Jesus 2000 years ago {John 3:1-6 still stands until Christ returns and then the earth will be destroyed by fire {2nd Peter 3:12}and the last Judgment and the New Heavens and earth {2nd Peter 3:13}
Peter said the new heavens and earth follows Christ coming and Rev chapter 21 the new heavens and earth appear and in Revelation chapter 20 is the 1000 year millennium {i.e.symbolic of the church age} and the 1st resurrection {i.e.spiritual resurrection of all believers in the church age}.
Dispensationalist are waiting on a millennium thats almost over.
Mercy.