The Daily Ma’amar of our Rebbe Rav Eliezer Berland shlit”a, from Erev Shabbat Bamidbar 25 Iyar 5783, courtesy of the “Hashem Hu HaElokim” leaflet:
Parashat Bamidbar — The Secret of the Census, the Secret of “According to their head count, according to their families, according to their fathers’ household”
That all the gentile nations, all of them, will come before the Holy One Blessed is He with the claim: Why doesn’t He offer to them to receive the Torah, because they also want to receive the Torah. The Gemara says: Hashem says to them, “Bring your family tree.” Because the gentiles do not have fathers, only mothers — it follows that not one has a family tree, because by most gentiles, the children are not theirs.
However, with the Jewish people, all of them are related to fathers, and therefore, only the Jewish people are fitting for the receiving of the Torah.