Those stones: that is, the stones that had been thrown into the unclean place.

He: the use of the singular pronoun in the last part of this verse has led some to suggest that the priest himself was required to put the new plaster (or mud) on the walls. But this is unlikely. This is probably another case of the third person singular pronoun being used to refer to some unknown person.

Quoted with permission from Péter-Contesse, René and Ellington, John. A Handbook on Leviticus. (UBS Helps for Translators). New York: UBS, 1990. For this and other handbooks for translators see here .