(30) Purified themselves.--Before consecration to God there must be purification from defilement. It is made emphatic that both priests and Levites purified themselves, that is, by offerings and ablutions (comp. 2Chronicles 29:15; Ezra 6:20): the gates and the wall by being sprinkled.

12:27-43 All our cities, all our houses, must have holiness to the Lord written upon them. The believer should undertake nothing which he does not dedicate to the Lord. We are concerned to cleanse our hands, and purify our hearts, when any work for God is to pass through them. Those that would be employed to sanctify others, must sanctify themselves, and set themselves apart for God. To those who are sanctified, all their creature-comforts and enjoyments are made holy. The people greatly rejoiced. All that share in public mercies, ought to join in public thanksgivings.And the priests and the Levites purified themselves,.... By washing their bodies and their clothes, perhaps by sprinkling the water of purification on them, see Numbers 8:6.