Romans 2:25-29, “Who or What is a Jew?”

See Verses 25-27... Paul is clearly saying that the circumcision of the flesh, by itself, is useless in reference to making us acceptable to a holy and righteous God.
Circumcision was the physical sign of a people set apart to obey God, to honor God; therefore, for a man to be circumcised and yet to dishonor God, nullified his being set apart for the purpose of bringing glory to God.
So, where did the covenant of circumcision come from? Why was it instituted? See Genesis 17:1-14... Notice (v. 1) Abram was 99 years old when God covenanted with him. Abram [means high or exalted father]. Abram was to live an obedient life in response to the covenant God was making with him; and this covenant would affect generations to come; in fact, (v. 4) God changed Abram’s name to Abraham [meaning father of many nations], although, at that time, Abraham had no children.
Abraham is the ancestral father of all Jews (v. 5), for they came through one of the sons of Jacob [Israel], he being the son of Isaac, who was the son of Abraham.
But Abraham was more importantly the spiritual father of all who would believe and obey the LORD, not only Israel, but also Gentiles (Galatians 3:28-29), “There is neither Jew nor Greek, slave nor free, male nor female, for you are all one in Christ Jesus. If you belong to Christ, then you are Abraham's seed [offspring, descendants], and heirs according to the promise.”
Notice in Genesis 17:7, this can’t just be talking about the covenant of circumcision that set the Jews apart from all the other nations on the earth; I believe this is also talking about the New Covenant through Christ’s shed blood, for it is through that covenant that eternal life is provided, making it an everlasting covenant.
Circumcision is the Old Covenant, established with Abraham, and therefore, Israel; Communion however is the New Covenant, established by Christ, with the Church, all who would believe, Jew and Gentile alike, people from every nation and language (1Corinthians 11:25), "This cup is the new covenant in My blood.”
The Old Covenant was one that declared biological ancestral affiliation with Abraham and later, with Jewish orthodoxy...
Last week I cited a passage from John 8:31-32, where Jesus said to some Jews, "If you hold to my teaching, you are really my disciples. Then you will know the truth, and the truth will set you free." In verse 33 they answered him, "We are Abraham's descendants and have never been slaves of anyone. How can you say that we shall be set free?"
In other words, the Jews were saying they didn’t need to be set free from slavery or bondage, because they were Abraham’s children; but, the New Covenant (through Christ’s blood) is entered into by personal recognition and repentance of sin, both confessing and professing faith in Jesus Christ, as Lord and Savior.
See Romans 2:28... There is no nation or individual who has been set apart eternally by God, through a covenant requiring the circumcision of one’s flesh.
But, a person can be a descendant of Abraham in one of several ways:
1. You can be a descendant by ancestral blood, through birth to one who is a blood related to Abraham.
2.You can be a descendant by spiritual birth ancestry, through the shed blood of Christ (Galatians 3:26-29), “You are all sons of God through faith in Christ Jesus, for all of you who were baptized into Christ have clothed yourselves with Christ. There is neither Jew nor Greek, slave nor free, male nor female, for you are all one in Christ Jesus. If you belong to Christ, then you are Abraham's seed [offspring], and heirs according to the promise.”
3.You can be a descendant by both ancestral blood and the blood of Christ, and there are many “Messianic” [born again, believing] Jews today.
God’s Word says (1Corinthians 15:50) “flesh and blood cannot inherit the kingdom of God. Jesus, speaking to Nicodemus (John 3:3) said, “unless [you] are born again [born of God], you will not see the kingdom of God,” (v. 4) in fact, “unless you are born of the Spirit [you] cannot enter the kingdom of heaven.”
A person is born again, born from above, born of God’s Spirit, when they believe, confess, and receive Jesus Christ as our Lord and Savior, (John 1:12-13) “Yet to all who received him, to those who believed in his name, he gave the right to become children of God— children born not of natural descent, nor of human decision or a husband's will, but born of God.”
Hebrews 11:8-16, “By faith Abraham, when called to go to a place he would later receive as his inheritance, obeyed and went, even though he did not know where he was going. By faith he made his home in the promised land like a stranger in a foreign country; he lived in tents, as did Isaac and Jacob, who were heirs with him of the same promise. For he was looking forward to the city with foundations, whose architect and builder is God. By faith Abraham, even though he was past age--and Sarah herself was barren--was enabled to become a father because he considered him faithful who had made the promise. And so from this one man, and he as good as dead, came descendants as numerous as the stars in the sky and as countless as the sand on the seashore. All these people were still living by faith when they died. They did not receive the things promised; they only saw them and welcomed them from a distance. And they admitted that they were aliens and strangers on earth. People who say such things show that they are looking for a country of their own. If they had been thinking of the country they had left, they would have had opportunity to return. Instead, they were longing for a better country--a heavenly one. Therefore God is not ashamed to be called their God, for he has prepared a city for them.”
Revelation 21:1-4, “Then I saw a new heaven and a new earth, for the first heaven and the first earth had passed away, and there was no longer any sea. I saw the Holy City, the new Jerusalem, coming down out of heaven from God, prepared as a bride beautifully dressed for her husband. And I heard a loud voice from the throne saying, "Now the dwelling of God is with men, and he will live with them. They will be his people, and God himself will be with them and be their God. He will wipe every tear from their eyes. There will be no more death or mourning or crying or pain, for the old order of things has passed away.”
See Romans 2:29... True Jews are not produced by anything resulting from human effort or construct.
Colossians 2:6-17, “So then, just as you received Christ Jesus as Lord, continue to live in him, rooted and built up in him, strengthened in the faith as you were taught, and overflowing with thankfulness. See to it that no one takes you captive through hollow and deceptive philosophy, which depends on human tradition and the basic principles of this world rather than on Christ. For in Christ all the fullness of the Deity lives in bodily form, and you have been given fullness in Christ, who is the head over every power and authority. In him you were also circumcised, in the putting off of the sinful nature, not with a circumcision done by the hands of men but with the circumcision done by Christ, having been buried with him in baptism and raised with him through your faith in the power of God, who raised him from the dead. When you were dead in your sins and in the uncircumcision of your sinful nature, God made you alive with Christ. He forgave us all our sins, having canceled the written code, with its regulations, that was against us and that stood opposed to us; he took it away, nailing it to the cross. And having disarmed the powers and authorities, he made a public spectacle of them, triumphing over them by the cross. Therefore do not let anyone judge you by what you eat or drink, or with regard to a religious festival, a New Moon celebration or a Sabbath day. These are a shadow of the things that were to come; the reality, however, is found in Christ.”
Clearly, a true “Jew” is an offspring of Abraham through faith and belief in Jesus Christ. So, there are Jews and then there are Jews; but neither circumcision, blood ancestry, practice of religion, strict adherence to the Law, or any other human product, activity, or acquisition can produce acceptability to God or make anyone a child of God, a member of God’s family, part of God’s church, or a citizen of God’s eternal kingdom.
Colossians 3:1-4, “Since, then, you have been raised with Christ, set your hearts on things above, where Christ is seated at the right hand of God. Set your minds on things above, not on earthly things. For you died, and your life is now hidden with Christ in God. When Christ, who is your life, appears, then you also will appear with him in glory.”
Colossians 3:16-17, “Let the word of Christ dwell in you richly as you teach and admonish one another with all wisdom, and as you sing psalms, hymns and spiritual songs with gratitude in your hearts to God. And whatever you do, whether in word or deed, do it all in the name of the Lord Jesus, giving thanks to God the Father through Him.”
So, who are true heavenly descendants of Abraham? Would that be the Jews, the blood ancestors of Abraham who are known as the nation of Israel today? No!
The eternal descendants of Abraham, the man who (Romans 4:3), “believed God and it was credited to him as righteousness,” are all the true believers and followers of Christ [Christians, the Family of God], (Galatians 3:29), “Abraham's [descendants], and heirs according to the promise.” What promise? The promise of eternal life in heaven with God! Abraham is the patriarch of the true Family of God now, and forever.
It was never God’s plan to validate an orthodox Jew, or a moral Gentile, whether they be Latino, Asian, African, Caucasian, Baptist, Lutheran, Presbyterian, Methodist, or anything else. God’s plan is for us to be born-again by God’s Spirit, forgiven all our sins and granted eternal life, by confessing, believing in, and following Jesus Christ, God’s Son: crucified, resurrected, and coming again.