Brit Bnai Noach from the Torah
The contrast between the 1st book of Moses and the other 4 books, the 1st addresses a man and his family's relationship with the Ancient of Days whereas the latter 4 books concerns the nation of Israel's relationship with the Ancient of Days. Even more fundamental, the 1st book of Moses addresses the Brit Bnai Noach whereas the latter books address the Brit Bnai Israel. The Talmud teaches that the Avot kept all the commandments yet the 1st book for the most part does not mention commandments! The Avot cut a covenant with foreigners. Who exactly were these foreigners? The Avot cut a brit with other Bnai Noach!
In the 2nd book of Moses, the Torah says: a new king that did not know Yosef. The Talmud debates this verse. The story of Yosef speaks about theft and oppression like that which the Torah spoke of the world being full of theft and oppression and of Hashem's regret of having Created the world. The government of Yosef obviously was a Bnai Noach Government. Hence if a new king arose that did not know Yosef this must mean that the king of Egypt had abandoned the Brit Bnai Noach. Hence the story of Exodus that speaks of the theft and oppression of Pharaoh and his government. The Talmud teaches that the nations abandoned the Brit Bnai Noach. A source for this teaching: the Aggadata and Midrash that teach concerning the revelation of Torah at Sinai that Hashem asked Esau and Ishmael if they would accept this Torah and they refused. Who were the descendants of Avraham? If Avraham was a Bnai Noach his descendants also were a Bnai Noach. The revelation of the Torah at Sinai being an obvious extension of the Brit Bnai Noach because if not how could the Talmud teach that the Avot kept all the commandments. If the Avot kept all the commandments and were Bnai Noach how many commandment to Bnai Noach observe today?
The majority opinion as held by Rav Shwartz of the Nascent Sanhedrin being the Talmudic teaching that since the nations abandoned the Brit Bnai Noach that the nations today have no commandment to keep the commandments of the Torah and that the reward given for keeping the commandment, that a person which has no commandment to keep these commandments being obviously less than the reward given to a person that has the commandment to keep the commandments. The oath before the judges its purpose: to restore the original status of the non-Bnai Brit peoples to being Bnai Brit peoples.
My opinion, that time is not linear concerning the Torah, that every generation has the opportunity to accept or reject the brit of Torah. That if the people of this generation choose to accept the Oath-Brit of Sinai than these people follow in the foot steps of the fathers of Israel that observed ALL the commandment! At Mt. Sinai the nation of Israel became a new creation and cut a brit, that today if the nations reject the folly of their fore-fathers and accept the Torah that they too shall establish a new creation upon this earth.