The Oven of Achnai
Rabbi Eliezer calls on a carob tree, a canal and the walls of the beis midrash to prove his ruling, but Rabbi Yehoshua and the Sages refuse to accept such proofs.
The Gemara records that there was a dispute between Rebbe Eliezer and the Sages regarding the halachic status of a certain type of oven (Bava Metzia 59b). Rebbe Eliezer brought all sorts of proofs to his opinion, but the Sages rejected them. Rebbe Eliezer then exclaimed, “If the law is as I say, may this carob tree prove it.” The carob tree was uprooted from its place a distance of 100 cubits. They said to him, “One cannot prove anything from a carob tree.”
Said Rebbe Eliezer to them, “If the law is as I say, may a canal prove it.” The water in the nearby canal began to flow backwards. Said they to him, “One cannot prove anything from a canal.”
Said he to them, “If the law is as I say, then may the walls of the house of study prove it.” The walls of the house of study began to cave in.
Rabbi Yehoshua rebuked the walls. “If Torah scholars are debating a point of Jewish law, what are your qualifications to intervene?”
The walls did not fall, in deference to Rabbi Yehoshua, nor did they straighten up, in deference to Rebbe Eliezer. They remained at a slant.