The Oven of Akhnai and the Anxiety of Rabbinic Authority

[Regarding a certain kind of oven, R. Eliezer rules that it is ritually pure and the sages rule that it is ritually impure.] It was taught: On that day, R. Eliezer responded with all possible responses, but they did not accept them from him. He said to them, "If the law is as I say, let this carob [tree] prove it." The carob uprooted itself from its place and went 100 cubits-and some say 400 cubits. They said to him, "One does not bring proof from a carob." The carob returned to its place. He said to them, "If the law is as I say, let the aqueduct prove it." The water flowed backward. They said to him, "One does not bring proof from water." The water returned to its place. He said to them, "If it [the law] is as I say, let the walls of the academy prove it." The walls of the academy inclined to fall. R. Joshua rebuked them, "When sages argue with one another about matters of law, what is it to you?" It was taught: They did not fall out of respect for R. Joshua, and they did not straighten up out of respect for R. Eliezer, and they are still inclined. He said to them, "If it is as I say, let it be proved from Heaven." A heavenly voice went forth and said, "What is your problem with R. Eliezer, since the law is like him in every place?" R. Joshua stood up on his feet and said, "It is not in Heaven" (Deuteronomy 30:12). What is "It is not in Heaven?" R. Jeremiah said, "We do not listen to a heavenly voice, since you already gave it to us on Mt. Sinai and it is written there, "Incline after the majority" (Exodus 23:2). R. Nathan came upon Elijah. He said to him, "What did the Holy One do at the time [of R. Joshua's and R. Jeremiah's bold statements]?" [Elijah] said to him, He laughed and said, "My children have conquered me, my children have conquered me."

But what is the reason behind the position of Rabbi [Judah that Torah law should prevail? This is his reasoning:] According to Torah law the husband may nullify the bill of divorce but [the rabbis] ruled that he may not nullify it. Now do rabbinic rulings uproot a rule of the Torah? (vedivrehen 'oqrin divre torah?!).

Akiva, even if you repeat the words "with oil" the whole day long I shall not listen to you; rather, the half log of oil of the thank offering, the quarter log of oil of the nazirite and the eleven days between menstrual periods are [each a] halakhah le-Moshe mi-Sinai.

(8) Rabban Gamliel had a diagram of the different forms of the moon drawn on a tablet that hung on the wall of his attic, which he would show to the laymen who came to testify about the new moon but were unable to describe adequately what they had seen. And he would say to them: Did you see a form like this or like this? There was an incident in which two witnesses came to testify about the new moon, and they said: We saw the waning moon in the morning in the east, and that same day we saw the new moon in the evening in the west. Rabbi Yoḥanan ben Nuri said: They are false witnesses, as it is impossible to see the new moon so soon after the last sighting of the waning moon. However, when they arrived in Yavne, Rabban Gamliel accepted them as witnesses without concern.

R. Nahman bar Yaakov (late third century C.E.) in the name of Rav (early third century C.E.): if she remarries on the basis of two witnesses, then even if he [the first husband] should come, they say to him "you are not he" [i.e., we do not legally recognize you].