JOHN 3:1 regarding Israel, is a TIME-BASED issue.
All Born Again activity was and is "in Christ"--the timing of which, as with Paul who said "I was crucified with Christ" (past tense)--occurred during the time of Christ's receiving the Holy Spirit when baptized by John in the Jordan. Which, by God's timing--not the timing of this world--meant all were (fore and past tense) born again "with Christ"--for all who are saved are "in Christ."
Therefore, all of the house of Israel whom Christ first came for was born of the Spirit with Christ, which He "finished"; and afterward that an "other fold" of the Gentiles, which He "must also bring", were also born again of the Spirit with Christ. "But" as Paul also said and clarified, "but each one in his own order." Which was to say, "each one (individual) in his own" time in the order of history.
In other words, "rightly dividing" the events of God from the times of this world, Israel was born again of the spirit of God before-the-fact, and the Gentiles after-the-fact. Which, gives credence to the scientific fact that time is an illusion. Such is the "all truth" of God according to "time no longer" revelation.