16:12-15 Moses summoned Dathan and Abiram to bring their complaints; but they would not obey. They bring very false charges against Moses. Those often fall under the heaviest censures, who in truth deserve the highest praise. Moses, though the meekest man, yet, finding God reproached in him, was very wroth; he could not bear to see the people ruining themselves. He appeals to God as to his own integrity. He bade them appear with Aaron next morning, at the time of offering the morning incense. Korah undertook thus to appear. Proud ambitious men, while projecting their own advancement, often hurry on their own shameful fall.

15. Moses was very wroth—Though the meekest of all men [Nu 12:3], he could not restrain his indignation at these unjust and groundless charges; and the highly excited state of his feeling was evinced by the utterance of a brief exclamation in the mixed form of a prayer and an impassioned assertion of his integrity. (Compare 1Sa 12:3).

and said unto the Lord, Respect not thou their offering—He calls it their offering, because, though it was to be offered by Korah and his Levitical associates, it was the united appeal of all the mutineers for deciding the contested claims of Moses and Aaron.