Moses took Korah's transgression much to heart, for he thought to himself that perhaps, after the many sins of Israel, he might not succeed in obtaining God's pardon for them. He did not therefore have this matter decided immediately, but admonished the people to wait until the following day, having a lingering hope that Korah's horde, given time for calm reflection, might themselves perceive their sin to which an excess of drink might have carried them away. Hence he said to them: "I may not now appear before the Lord, for although He partakes of neither food nor drink, still He will not judge such actions of ours as we have committed after feasting and revelling. But 'to-morrow the Lord will show who are His.'  Know ye now that just as God has set definite bounds in nature between day and night, between light and darkness, so also has He separated Israel from the other nations, and so also has he separated Aaron from the rest of Israel. If you can obliterate the boundary between light and darkness, then only you remove the boundary of separation between Israel and the rest, but not otherwise. Other nations have many religions, many priests, and worship in many temples, but we have one God, one Torah, one law, one altar, and one high priest, whereas ye are two hundred fifty men, each of whom is imbued with the desire of becoming the high priest, as I too should like to be high priest, if such a thing were possible. But to prove Aaron's claim to his dignity, 'this do; take you censers, Korah, and all his company; and put fire therein, and put incense upon them before the Lord to-morrow.' The offering of incense is the most pleasant offering before the Lord, but for him who hath not been called this offering holds a deadly poison, for it consumed Nadab and Abihu. But I exhort ye not to burden your souls with a deadly sin, for none but the man God will choose as high priest out of the number of you will remain alive, all others will pay with their lives at the offering of incense." These last words of Moses, however, far from restraining them, only strengthened Korah in his resolve to accomplish his undertaking, for he felt sure that God would choose him, and none other. He had a prophetic presentiment that he was destined to be the forefather of prophets and Temple singers, and for this reason thought he was specially favored by God.
When Moses perceived that Korah was irreclaimable, he directed the rest of his warning to those other Levites, the men of Korah's tribe, who, he feared, would join Korah in his rebellion. He admonished them to be satisfied with the honors God had granted them, and not to strive for priestly dignity. He concluded his speech with a last appeal to Korah to cause no schism in Israel, saying; "Had Aaron arbitrarily assumed the priestly dignity, you would do right to withstand his presumption, but it was God, whose attributes are sublimity, strength, and sovereignty, who clothed Aaron with this dignity, so that those who are against Aaron are in reality against God." Korah made no answer to all these words, thinking that the best course for him to follow would be to avoid picking an argument with so great a sage as Moses, feeling sure that in such a dispute he should be worsted and, contrary to his own conviction, be forced to yield to Moses.
Moses, seeing that is was useless to reason with Korah, sent a messenger to Dathan and Abiram,  summoning them to appear before his court. He did this because the law required that the accused be summoned to appear before the judge, before the judgement may be passed upon him, and Moses did not wish these men to be punished without a hearing.  These, however, made answer to the messenger sent by Moses, "We will not come up!" This shameless answer held an unconscious prophecy. They went not up, but, as their end showed, down, to hell. Not only, moreover, did they refuse to comply with Moses' demand, they sent the following message in answer to Moses: "Why dost thou set thyself up as master over us? What benefit didst thou bring to us? Thou didst lead us out of Egypt, a land 'like the garden of the Lord,' but hast not brought us to Canaan, leaving us in the wilderness where we are daily visited by the plague. Even in Egypt didst thou try to assume the leadership, just as thou doest not. Thou didst beguile the people in their exodus from Egypt, when thou didst promise to lead them to a land of milk and honey; in their delusion they followed thee and were disappointed. Now dost thou attempt to persuade us as thou didst persuade them, but thou shalt not succeed, for we will not come and obey thy summons." 
The shamelessness of these two men, who declined even to talk about their transgression with Moses, aroused his wrath to the uttermost, for a man does get a certain amount of satisfaction out of discussing the dispute with this opponents, whereas he feels badly if he cannot discuss the matter. In his anger he said to God: "O Lord of the world! I well know that these sinners participated in the offerings of the congregation that were offered for all Israel, but as they have withdrawn themselves from the community, accept not Thou their share of the offering and let it not be consumed by the heavenly fire. It was I whom they treated so, I who took no money from the people for my labors, even when payment was my due. It is customary for anyone who works for the sanctuary to receive pay for his work, but I traveled to Egypt on my own ass, and took none of theirs, although I undertook the journey in their interests. It is customary for those that have a dispute to go before a judge, but I did not wait for this, and went straight to them to settle their disputes, never declaring the innocent guilty, or the guilty innocent."
When he now perceived that his words had no effect upon Korah and his horde, he concluded his words with a treat to the ring leaders: "Be thou and all thy company before the Lord, thou and they, and Aaron, to-morrow."
Korah spent the night before the judgement in trying to win over the people to his side, and succeeded in so doing. He went to all the other tribes, saying to them: "Do not think I am seeking a position of honor for myself. No, I wish only that this honor may fall to the lot of each in turn, whereas Moses is now king, and his brother high priest." On the following morning, all the people, and not Korah's original company alone, appeared before the Tabernacle and began to pick quarrels with Moses and Aaron. Moses now feared that God would destroy all the people because they had joined Korah, hence he said to God: "O Lord of the world! If a nation rebels against a king of flesh and blood because ten or twenty men have cursed the king or his ambassadors, then he sends his hosts to massacre the inhabitants of the land, innocent as well as guilty, for he is not able with certainty to tell which among them honored the king and which among them cursed him. But Thou knowest the thought of man, and what his heart and kidneys counsel him to do, the workings of Thy creatures' minds lie open before Thee, so that Thou knowest who had the spirit of each one.' Shall one man sin, and wilt thou be wroth with all the congregation?'" God hereupon said to Moses  "I have heard the prayer for the congregation. Say then, to them, 'Get you up from about the Tabernacle of Korah, Dathan, and Abiram.'" 
Moses did not immediately carry out these instructions, for he tried once again to warn Dathan and Abiram of the punishment impending upon them, but they refused to give heed to Moses, and remained within their tents. "Now," said Moses, "I have done all I could, and can do nothing more." Hence, turning to the congregation, he said:  "Depart, I pray you, from the tents of these wicked men, that even in their youth deserved death as a punishment for their actions. In Egypt they betrayed the secret of my slaying an Egyptian: at the Red Sea it was they that angered God by their desire to return to Egypt; in Alush they broke the Sabbath, and now they trooped together to rebel against God. They now well deserve excommunication, and the destruction of all their property. 'Touch, therefore, nothing of theirs, lest ye be consumed in all their sins.'" 
The community obeyed the words of Moses and drew back from the dwellings of Dathan and Abiram. These, not at all cowed, were not restrained from their wicked intention, but stood at the doors of their tents, abusing and calumniating Moses. Moses hereupon said to God: "If these men die upon their beds like all men, after physicians have attended to them and acquaintances have visited them, then shall I publicly avow 'that the Lord hath not sent me' to do all these works, but that I have done them of mine own mind." God replied: "What wilt thou have Me do?" Moses: "If the Lord hath already provided the earth with a mouth to swallow them, it is well, if not, I pray Thee, do so now." God said: "Thou shalt decree a thing, and it shall be established unto thee." 
Moses was not the only one to insist upon exemplary punishment of the horde of Korah. Sun and Moon appeared before God, saying: "If Thou givest satisfaction to the son of Amram, we shall set out on our course around the world, but not otherwise." God, however, hurled lightnings after them, that they might go about their duties, saying to them: "You have never championed My cause, but not you stand up for a creature of flesh and blood." Since that time Sun and Moon have always to be driven to duty, never doing it voluntarily because they do not wish to look upon the sins of man upon earth.