Aaron could not take part in the burial of Nadab and Abihu, for a high priest is not permitted to take part in a funeral procession, even if the deceased be a near kinsman. Eleazar and Ithamar, also, the surviving sons of Aaron, were not permitted to mourn or attend the funeral on the day of their dedication as priests, so that Aaron's cousins, the Levites Mishael and Elzaphan, the next of kin after these had to attend to the funeral.
These two Levites were the sons of a very worthy father, who was not only by descent a near kinsman of Aaron, but who was also closely akin to Aaron in character. As Aaron pursued peace, so too did his uncle Uzziel, father to Mishael and Elzaphan. Being Levites they might not enter the place where the heavenly fire had met their cousins, hence an angel had thrust Nadab and Abihu out of the priestly room, and they did not die until they were outside it, so that Mishael and Elzaphan might approach them.