Korach - Rishon
Korach Has Seniority
A rebellion was started by a disgruntled Levite named Korach, from the family of Kehos. (Rashi cites the Midrash that the reason for his rebellion was that Korach felt passed over for a promotion when he wasn’t selected head of his Tribe. He then accused Moshe of nepotism in making his own brother High Priest.) Assisted by Dasan, Aviram and Ohn from the Tribe of Reuben, he gathered a delegation of 250 prominent people to oppose Moshe. "The entire nation is holy," they started, "so why have you set yourself above everybody else?"
Moshe was mortified by the accusation. "You think one of you should be High Priest? Fine. In the morning, G-d will make His preference known. Let everyone offer incense and G-d will pick whomever He wants. But just to let you dissatisfied Levites know, you ask too much. G-d has already given you a special role and it's not enough for you? You're not complaining against me, but against Him!"
Moshe summoned Dasan and Aviram, who had been troublemakers since Egypt. They refused to come, saying that Moshe had caused the people enough grief.