There is no such thing as a "spiritual" Jew or Israelite.
disps can't deal with Galatians
Galatians 6
Not Circumcision but the New Creation
11See what large letters I use as I write to you with my own hand!
12Those who want to impress people by means of the flesh are trying to compel you to be circumcised. The only reason they do this is to avoid being persecuted for the cross of Christ. 13Not even those who are circumcised keep the law, yet they want you to be circumcised that they may boast about your circumcision in the flesh. 14May I never boast except in the cross of our Lord Jesus Christ, through whicha the world has been crucified to me, and I to the world. 15Neither circumcision nor uncircumcision means anything; what counts is the new creation. 16Peace and mercy to all who follow this rule—to the Israel of God.
17From now on, let no one cause me trouble, for I bear on my body the marks of Jesus.
18The grace of our Lord Jesus Christ be with your spirit, brothers and sisters. Amen.
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And upon the Israel of God - The true church of God; all who are his true worshippers; see the note at Romans 2:28-29; Romans 9:6, note. - Barnes'
The Israel of God - The true Christians, called here the Israel of God, to distinguish them from Israel according to the flesh. See the notes on Romans 2:29; Romans 4:12 (note) - Clarke
and upon the Israel of God; which is a further description of the persons, for whom he prays for these blessings; and is not to be understood by way of distinction from them, but as an amplification of their character; and as pointing out the Israel, by way of emphasis, the Israel, or Israelites indeed, the spiritual Israel, as distinct from Israel according to the flesh; see 1 Corinthians 10:18. The "Israel of God", or as the Arabic version reads it, "Israel the propriety of God"; which he has a right unto, and a claim upon; who are chosen by him, Israel his elect; who are redeemed by him, out of every kindred, tongue, people, and nation; who are called by his grace, and are styled Israel his called; who are justified in his Son, and by his righteousness; and for whose sake he is exalted as a Prince and a Saviour, to give them repentance and remission of sin; and who are, or will be saved by him, with an everlasting salvation; and is a name that includes all God's elect, whether Jews or Gentiles: though it may have a particular respect to such of the Israelites, or Jews, God had foreknown and reserved for himself; and who believed in Christ, and walked as new creatures, without confidence in the flesh. The Jews themselves own, that strangers, or proselytes, shall be called by the name of Israel; so they (b) explain Isaiah 44:5, latter part. - Gill
Upon the true Israel, whose praise is from God and not from men; Ro 2:29. - Geneva
Israel of God—not the Israel after the flesh, among whom those teachers wish to enrol you; but the spiritual seed of Abraham by faith (Ga 3:9, 29; Ro 2:28, 29; Php 3:3). - JFBBC
6:16-18 A new creation to the image of Christ, as showing faith in him, is the greatest distinction between one man and another, and a blessing is declared on all who walk according to this rule. - Henry
And upon the Israel of God. Rather, Even upon, etc. The Greek word kai often means even, and does here, as the Israel of God does not differ from those who follow this rule. - PNT
We may compare in particular Ephesians 6:24, "Grace be with all them that love our Lord Jesus Christ in uncorruptness," not only as similar in construction, requiring the like suppletion of "be," but also as another instance in which the apostle pronounces his pastoral benediction with a certain limitation, specifying those only who sincerely love Jesus Christ. The limitation in these two cases only implied is in 1 Corinthians 16:22 converted into a distinctly expressed anathema upon those who do not love Christ.
The words, "and upon the Israel of God," seem to be an echo of the "peace upon Israel (εἰρήνη ἐπὶ τὸν Ἰσραήλ)," which, in the Septuagint, closes the hundred and twenty-fifth and hundred and twenty-eighth psalms. The addition of the words, "of God," seems intended pointedly to distinguish the "Israel" which the apostle has m view from that which boasted itself as being Israel while it was not, and also from the false brethren (ψευδαδελφοί, Galatians 2:4) in the Christian Church, who were for linking themselves with the false Israel. The addition is not merely honorific, as in the expression, "the Church of God" (1 Corinthians 1:2; 2 Corinthians 1:1; 10:32; 11:22; 15:9), but distinctive as well - that which alone God views and loves as "Israel" - to wit, the entire body of real believers in Christ, who, as portrayed in this Epistle, are "children of promise after the fashion of Isaac" (Galatians 4:28), Abraham's seed and heirs of the promise" (Galatians 3:29), and the children of "the upper Jerusalem, which is our mother" (Galatians 4:26). - Pulpit
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any truly born again believer who has been led through the God-breathed Scriptures by the Holy Spirit
knows they are the Israel of God, accepted in the Beloved.
the Spirit testifies to them, continually
the Spirit does
not testify of a Mystery Gentile Grace Church Age Gap Parenthesis.