When Moses descended from Sinai, he there found his true servant Joshua, who had awaited him on the slope of the mountain throughout all the forty days during which Moses stayed in heaven, and together they repaired to the encampment. On approaching it, they heard cries of the people, and Joshua remarked to Moses: "There is a noise of war in the camp," but Moses replied: "Is it possible that thou, Joshua, who art one day destined to be the leader of sixty myriads of people, canst not distinguish among the different kinds of dins?
This is no cry of Israel conquering, nor of their defeated foe, but their adoration of an idol." When Moses had now come close enough to the camp to see what was going on there, he thought to himself: "How now shall I give to them the tables and enjoin upon them the prohibition of idolatry, for the very trespassing of which, Heaven will inflict capital punishment upon them?" Hence, instead of delivering to them the tables, he tried to turn back, but the seventy elders pursued him and tried to wrest the tables from Moses.
But his strength excelled that of the seventy others, and he kept the tables in his hands, although these were seventy Seah in weight. All at once, however, he saw the writing vanish from the tables, and at the same time became aware of their enormous weight; for while the celestial writing was upon them, they carried their own weight and did not burden Moses, but with the disappearance of the writing all this changes.
Now all the more did Moses feel loath to give the tables without their contents to Israel, and besides he thought: "If God prohibited one idolatrous Israelite from partaking of the Passover feast, how much more would He be angry if I were now to give all the Torah to an idolatrous people?" Hence, without consulting God, he broke the tables. God, however, thanked Moses for breaking the tables.