"My overall point here is that Abraham had seven sons through Hagar and Ketorah. However, the covenant with the land and seed promises was not passed down through the sons but it was passed down from G-d to Abraham through the child of the promise, Isaac. And from Isaac it was passed down to Jacob. Isaac's other son Esau was not a recipient of the covenant promises. He ended up becoming the father of the Edomites. From Jacob, the covenant was passed down to his twelve sons, who passed it down to the twelve tribes of Israel who became known as the Jewish people. What are some implications of tracing this early history of the origins of G-d's covenant with the Jewish people?
One implication is that being a member of the covenant people is not synonymous with being a physical descendant of Abraham. There were many physical descendants of Abraham in the family tree including the twelve tribes of Ishmael and the descendants of Ketorah. However, they were not part of the covenant people. They were not recipients of the covenant or conveyors of the covenant with the land and seed promises. This said I think it is reasonable to assume that all of these descendants of Abraham were blessed in other ways like Ishmael was by virtue of their relationship to Abraham. According to Genesis, the recipients and conveyors of the covenant with its land and seed promises were the physical descendants of Abraham, Isaac, and Jacob--that is the twelve tribes of Israel later known as the Jewish people. By the way, every Shabbat when we come together to worship the L-rd you may notice that in our prayers that we put on the screen and that are in our siddurs we often refer to the G-d of Abraham, Isaac, and Jacob and not just the G-d of Abraham. And I want to--I want that to catch your attention next time because it's actually very significant. When we refer to the G-d of Abraham, Isaac, and Jacob, we're talking about the G-d of the covenant that was passed down through the specific lineage from Abraham to Isaac to Jacob to the twelve tribes.
A second implication of what we have learned from the Genesis account is that being a physical descendant of Abraham, Isaac, and Jacob is not synonymous with being a member of the covenant people. We learn that a Jew who does not circumcise his son cuts his son off from G-d's covenant. As Adonai puts it, in Genesis chapter seventeen verse fourteen, any uncircumicsed male who has not been circumcised in the flesh will be cut off from his people, he has broken my covenant. Is there a way to be cut off from the Jewish people? Genesis seventeen makes it clear that not circumicsing one's son cuts him off from the covenant people. This would explain why HaShem was on the verge of killing Moses on his way from Midian to Egypt. It is because Moses did not circumicse his sons. We're told in Exodus chapter four, verses twenty-four through twenty-six, at a lodging place on the way, Adonai met Moses and was about to kill him but Tzipporah took a flint knife, cut off her son's foreskin, and touched Moses' feet with it. Surely you are a bridegroom of blood to me, she said. So the L-rd let him alone. At that time she said bridegroom of blood referring to circumcision. Here the L-rd was about to kill Moses because he was cutting off his children from the covenant by not circumcising them, perhaps because Moses was raised in Pharoah's household he didn't give it much priority. He probably didn't think it was such a big deal. But Moses' wife Tzipporah knew exactly what they had neglected. And how did she know? Remember! She was a Midianite! A descendant of Ketorah. And so she was probably aware through the tradition of her own people who were descendants of Abraham that G-d commanded Abraham and his descendants to be circumcised and that those who were not circumicsed would be cut off from the covenant…and….their people. In other words, according to Genesis chapter seventeen, Jewish identity is not simply a matter of physical descent. It is also a matter of choice, a decision on the part of the Jewish parents, to enter their child into the covenant. It is the committment to l'dor v'dor, from generation to generation. In this sense, all Jews are Jews by choice.
This is why the Jewish community does not regard DNA testing as a means of determining Jewish identity. DNA testing only indicates the existence of Jewish ancestry perhaps from centuries or even thousands of years before. If the person tested was not raised as a Jew it is because their ancestors stopped passing on the covenant to their children. Sometimes this was even against their own wishes such as in the case of the Inquisition where the Gentile Christian church forcibly converted Jews to Christianity and required baptized Jews to renounce all associations with Jews and Judaism. The punishment for circumcising their sons was in many cases death. As we approach the High Holy days and the Kol Nidre service in particular we need to feel the weight of the burden that our people during the Inquisition carried and sympathize with the decisions they were forced to make in order to survive. Bearing this in mind, I would only say that based on Genesis chapter seventeen, in general when Jewish parents do not pass on the covenant sign, their children and their children's children become cut off from Kol Yisrael and the covenant G-d made with Abraham.
When people come to Tikvat Israel with this kind of background where there was a break in the covenant at some point in their family history, I encourage them not to identify as Jews but to identify as Gentile followers of Yeshua who have Jewish ancestry and who feel a special connection to the Jewish people because of this. Why do I encourage this particular identification? It is because we need to be accurate and Biblical and the reality is that the covenant was broken long ago. In cases of duress like the Inquisition, I see this as a little more of a gray area. If the family continued to identify in some way secretly as Jews and this can be documented. This said, in the traditional Jewish community, the only way for a person in this kind of situation to restore their Jewish identity would be to go through a formal process of conversion in order to rejoin the Jewish people." from: http://www.tikvatisrael.com/library/sermon/romans_225_the_value_of_circumcision/
Do you agree or disagree with Rabbi Rudolph?