In the King James Bible here is what is stated: For he is not a Jew, which is one outwardly; neither is that circumcision, which is outward in the flesh: But he is a Jew, which is one inwardly; and circumcision is that of the heart, in the spirit, and not in the letter; whose praise is not of men, but of God.
What was the reason for this comment and how should it be interpreted? Should it also be used to nullify God's promises to Abraham, Isaac, and Jacob regarding the twelve tribes?
The entire second chapter of Romans is addressed to Jews, particularly those who believed that they were religious and keeping the commandments. But they were focused on the outward ceremonies and rituals, without carefully examining what was within the heart. And God is more concerned with the heart than with outward appearances and rituals.
The Pharisees were the epitome of strict Torah observance, going even as far as tithing mint and cumin (herbs). But they were not right with God. They were boasting of the Ten Commandments, but breaking them at the same time.
In view of this Paul defined the meaning of a true Jew. That person would be one who had repented and been converted. One who had been born again. Therefore he would have a new heart and a new spirit.
But this passage was not meant to nullify the Abrahamic Covenant as applicable to the land of Israel. Paul makes it perfectly clear in Romans 11 that at the Second Coming of Christ, "all Israel shall be saved". Since we know that only one-third of all the Jews in the world will be saved at that time, his meaning would be that every tribe belonging to Israel shall be saved. And this is confirmed in Ezekiel 48 where all twelve tribes are shown as dwelling in the land of Greater Israel.