Commentary for Numbers 26:9

אשר הצו WHO INCITED — i.e., who incited Israel, על משה AGAINST MOSES,

AND THE SONS OF ELIAB: NEMUEL, AND DATHAN, AND ABIRAM. THESE ARE DATHAN AND ABIRAM WHO [QUARRELLED AGAINST MOSES] etc. Scripture mentions this [episode leading to the death of Dathan and Abiram] in order to indicate that the whole inheritance of the Palluite family remained for Nemuel alone, because Dathan and Abiram [the other sons of Eliab] and all their belongings were swallowed up [in the earth, and hence Nemuel was the only surviving son of Eliab, who was in turn the only son of Pallu]. Or it may be, as our Rabbis have said,⁴⁰Baba Bathra 118 b. that [Dathan and Abiram’s death is mentioned here] to allude [to the fact] that they lost their share in the Land even though they were amongst those who came out of Egypt, and were therefore eligible to [receive] an inheritance.

הוא דתן ואבירם, "the same Datan and Aviram, etc." What did the Torah want to teach us by referring to Datan and Aviram at this point? If the Torah merely wanted to tell us that these two were the same Datan and Aviram we have encountered in connection with the rebellion of Korach, we knew this. It was hardly likely that two members of the tribe of Reuven both named Eliav each had two sons called Datan and Aviram. Moreover, their names did not need to appear here at all. None of the other families who had died before this census were mentioned in this sequence. Furthermore, why was the Torah so long-winded in telling us how these two brothers "incited in the company of Korach against Moses and Aaron when they incited against G'd?"