Rabbi Eliezer disputed with the sages as to whether a clay oven that had become impure, had been broken up, and then reassembled with sand between the pieces, was still impure or, having been broken, was now pure. After he offered all of his arguments to show that the oven was now pure and they were all rejected, he called upon a carob tree to prove the truth of his position. The carob tree promptly uprooted itself and was flung a great distance away. The sages responded that a carob tree had nothing to say in the disputes of legal scholars.
The argument continues, Eliezer is supported by two more miracles, each of which the sages insist is irrelevant. Finally he asks heaven to support him, and a voice form heaven announces that in all matters of the law Eliezer is correct. To which one of the sages replies (to God) "It is not in heaven." Or in other words, "butt out."
To make sense of the story so far, one needs a little background. Jewish law, like any system based on divine revelation, has an inherent problem with maintaining consistency. If the law is what God said, and different judges have different interpretations of what that is, then the judges will give different rulings on the same question. What God said is not determined by majority vote.
Early on, the legal scholars came up with a solution to this problem, based on their interpretation of a passage in the Torah, the first five books of the Old Testament. What God said was something that each legal scholar could determine for himself. But if they disagreed, what the law was was determined by majority vote of the scholars. Better that they risk getting the law wrong than that they end up disagreeing in their judgments. A scholar who disagreed was free to argue for his position, but when functioning as a judge he had to decide according to the view that had been established by the majority.
The story is happening at the end of a period of several generations in which the legal scholars were divided into two schools, the school of Hillel and the school of Shamai, which disagreed about details of the law but continued to each treat the other as legitimate. Eliezer was a leading figure in the school of Shamai; the "sages" in the story are scholars of the school of Hillel, which at that point was the larger of the two. The point of the first part of the story is that, even if Eliezer was correct in his interpretation of the law, what the law was was determined not by what position was correct but by what position was supported by the majority—and the majority was against him. The law is no longer in heaven to be determined by God but on earth, having been given by God to the legal scholars to interpret for themselves and define by majority vote.
Having rejected divine authority as a basis for the law—a decision which, according to another bit of the story, God himself approved of—the sages went on to put Rabbi Eliezer under ban. After which:
Said they, 'Who shall go and inform him?' 'I will go,' answered R. Akiba, 'lest an unsuitable person go and inform him, and thus destroy the whole world.' What did R. Akiba do? He donned black garments and wrapped himself in black, and sat at a distance of four cubits from him. 'Akiba,' said R. Eliezer to him, 'what has particularly happened to-day?' 'Master,' he replied, 'it appears to me that thy companions hold aloof from thee.' Thereupon he too rent his garments, put off his shoes, removed [his seat] and sat on the earth, whilst tears streamed from his eyes. The world was then smitten: a third of the olive crop, a third of the wheat, and a third of the barley crop. Some say, the dough in women's hands swelled up.
A Tanna taught: Great was the calamity that befell that day, for everything at which R. Eliezer cast his eyes was burned up. R. Gamaliel too was travelling in a ship, when a huge wave arose to drown him. 'It appears to me,' he reflected, 'that this is on account of none other but R. Eliezer b. Hyrcanus.' Thereupon he arose and exclaimed, 'Sovereign of the Universe! Thou knowest full well that I have not acted for my honour, nor for the honour of my paternal house, but for Thine, so that strife may not multiply in Israel! 'At that the raging sea subsided.Ima Shalom was R. Eliezer's wife, and sister to R. Gamaliel. From the time of this incident onwards she did not permit him to fall upon his face. Now a certain day happened to be New Moon, but she mistook a full month for a defective one. Others say, a poor man came and stood at the door, and she took out some bread to him. [On her return] she found him fallen on his face. 'Arise,' she cried out to him, 'thou hast slain my brother.' In the meanwhile an announcement was made from the house of Rabban Gamaliel that he had died.(from the Babylonian Talmud)
What about the ban? That corresponds to what really happened in the conflict between the two schools—the school of Hillel won out and effectively suppressed the rival school. The story seems to imply that that outcome was wrong—or if right, catastrophically right, resulting in mass destruction. God threatened to drown the leader of the sages for his role in what happened, even if persuaded not to, and God did kill him the first time Eliezer prayed—at least I assume that's what "falling on his face" refers to.
With any luck, one or more of the readers of the post will be more familiar with the subject than I am, and able to throw some light on the second half of the story.
Jewish law is not the only system to face the problem of establishing consistent law based on an authoritative source. The equivalent problem in U.S. law is constitutional interpretation, and the solution is rather like the Jewish solution. A judge or law professor is free to argue for his interpretation of the Constitution, but once the Supreme Court has voted on the subject a judge is required to rule according to its vote.
Sharia also claims to be deduced from religious sources rather than created by a ruler, legislator, or court. The split between the schools of Hillel and Shamai in Jewish law corresponds to the division among the four schools of Sunni Muslim law. In the Muslim case Shamai was never repressed. The four schools continued to regard each other as mutually orthodox for more than a thousand years—and still do.
Which suggests that legal uniformity may be less essential than one would expect.