All understanding comes from the writings of the prophets (Old Testament or Tanach: they are one and the same) in light of the Mashiach’s death for our sin, His burial and His resurrection the third day. The Law and the Prophets prophesy or foretell the Christ’s death for our sins, His burial and His resurrection the third day. Yeshua of Nazareth is the Mashiach.
Beloved, I want to write on this verse in particular, because from it comes the thought of Gentiles being spiritual Jews. This is a great error. The word “Jew” is a shortened word taken from those of the kingdom of Yudah. There was the kingdom of Yisrael (eleven tribes) and the kingdom of Yudah. The kingdom of Yudah is only one tribe, Yudah. The kingdom of Yisrael was conquered and dispersed by the Assyrians in 722 BC. The kingdom of Yudah was conquered and dispersed by the Babylonians in 586 BC. There was never a formal decree for the kingdom of Yisrael to return back to the land, as there was with Yudah to return back to the land by Cyrus 70 years after the judgment of Yerushalem by Nebuchadnezzar. Those of Yudah first returned back to the land and were primarily the inhabitants of the land of Yudah when Yeshua was born, lived, crucified, died, was buried and rose again. It was those of Yudah who were the primary inhabitants of the land when the Romans brought judgment purposed and foretold by God upon Yerushalem in 70 AD. So when we read the word “Jew” in the New Testament, this means mainly those of Yudah, the kingdom of Yudah. They had had the temple and the priesthood until the “not one stone left standing upon another” judgment of Yerushalem in 70 AD. “Jew” today has come to mean all the descendant of the twelve tribes whether of the eleven northern tribes, or the one southern tribe. There is much more I could say on this subject, but may I get to my point.
Going to Romans chapter 3 now. Gentiles are not spiritual Jews. Just as those of Yudah of the tribe of Yudah are not spiritual members of any other tribe, or spiritual Gentiles. They are only of the tribe of Yudah, and spiritually belong to no other. And all of the twelve tribes are of Yisrael. And the Gentiles, gowy (gow-ee) in the Hebrew, or more accurate “the nations” are not anything other than the nation they are. Now under the Torah a stranger could be of Yisrael, and abide with the inhabitants of a tribe, but not be a priest. They would be called of Yisrael, and dwell with a certain tribe. Now their children could marry and their children could then be of a certain tribe, depending on who they married. The gospel preached to Avraham is “in thy seed all the nations of the earth shall be blessed.” All the nations are called Gentiles (gowy) along with “the nation” called by the name of God, Yisrael. Yehovah gave Yacob’s sons and their descendants His name, as the name of their nation, Yisrael. There is no spiritual “this nation” or “that nation”. All nations are as God has ordained, so that He can equally without partiality bless all nations in the Mashiach. Yeshua of Nazareth is the Son of God raised from the dead, the Mashiach of the one true God. And the one true God is “Yehovah”, meaning “I am”, and “Elohiym”, meaning the “God of all gods”: there is none beside Him. And the only begotten Son of God sits at His right hand until He, God, makes His enemies his foot stool.
I will first say concerning Romans 3:28-29 this is hard passage to translate. I will give a clear interpretation in Spirit of the passage so there will be no place for error. The italics are my additions.
“Just because you are obviously a Jew in appearance (physical appearance or geneology), or obviously circumcised in the flesh, does not mean that you are circumcised in heart. For when a Jew is circumcised in heart, it is not obvious, but it is hidden. It is in spirit, and not in letter. And the Jew who is circumcised in heart does not have the praise of men, but the praise is from God.”
As you see, beloved, there is no “spiritual Jew” in this passage. Gentiles are not “spiritual Jews”, but out of Yudah, Yisrael, and Gentiles are “the children of promise”, the assembly of the living God, the saved of God who endure to the end. Whether Jew or Gentile the circumcision of the heart. Not all of Yisrael were of Yisrael, for two were of Yoseph. Read this last sentence carefully and read the scriptures of the prophets. (Old Testament, Tanach)