Charles Ellicott Commentary Numbers 16:37

"Speak unto Eleazar the son of Aaron the priest, that he take up the censers out of the burning, and scatter thou the fire yonder; for they are holy," — Numbers 16:37 (ASV)

Speak to Eleazar the son of Aaron ... — Aaron was shortly to be employed in an act of priestly service and intercession, for which he would have become disqualified had he been ceremonially defiled by contact with things pertaining to the dead.