tn This verb is a Piel perfect with vav (ו) consecutive; it continues the force of the imperative preceding it. This sanctification would be accomplished by abstaining from things that would make them defiled or unclean, and then by ritual washings and ablutions.

tn The form is a perfect 3cpl with a vav (ו) consecutive. It is instructional as well, but now in the third person it is like a jussive, “let them wash, make them wash.”