John Calvin on Leviticus 10:4-8

4. And Moses called Mishael and Elzaphan Lest Eleazar and Ithamar should carry “Se polluassent en portant les corps morts de leurs freres;” should pollute themselves by carrying the dead bodies of their brothers. — Fr. Blunt has a very ingenious conjecture that Mishael and Elzaphan were the very persons “defiled by the dead body of a man,” mentioned in Numbers 9:6, 7, and who therefore could not keep the Passover. “The Veracity of the Five Books of Moses.” Art. 14. But surely, out of such a large body of persons, there must have been many deaths daily, and consequently others would have been defiled besides Mishael and Elzaphan. forth the corpses, Moses commanded these others to anticipate them. It may also have been the case that all were stupified by terror. He forbids the father and brothers to mourn their death, not so much in accordance with the law, whereby all except the high priest were permitted to mourn for their own brother, as to prevent this memorable lesson from being obscured by their grief, since thus was the sanctity of their religion magnificently asserted. Nevertheless, God allowed the dead men to be bewailed by the people, lest the recollection of their punishment should too soon be lost.

When he forbids (Aaron Added from Fr. and his sons) to go out from the door of the tabernacle, he does not mean so to fix them to that place as to banish them from their own private tents, but he withholds them from all pollution which might have compelled them to desert or interrupt their duty.