14 In this way, you will set the Levites apart from the rest of the people of Israel, and the Levites will belong to me. 15 After this, they may go into the Tabernacle to do their work, because you have purified them and presented them as a special offering. 16 "Of all the people of Israel, the Levites are reserved for me. I have claimed them for myself in place of all the firstborn sons of the Israelites; I have taken the Levites as their substitutes. 17 For all the firstborn males among the people of Israel are mine, both of people and of animals. I set them apart for myself on the day I struck down all the firstborn sons of the Egyptians. 18 Yes, I have claimed the Levites in place of all the firstborn sons of Israel. 19 And of all the Israelites, I have assigned the Levites to Aaron and his sons. They will serve in the Tabernacle on behalf of the Israelites and make sacrifices to purify the people so no plague will strike them when they approach the sanctuary."
Matthew Henry's Commentary on Numbers 8:14-19
Commentary on Numbers 8:5-26
(Read Numbers 8:5-26)
Here we have directions for the solemn ordination of the Levites. All Israel must know that they took not this honour to themselves, but were called of God to it; nor was it enough that they were distinguished from others. All who are employed for God, must be dedicated to him, according to the employment. Christians must be baptized, ministers must be ordained; we must first give ourselves unto the Lord, and then our services. The Levites must be cleansed. They must be clean that bear the vessels of the Lord. Moses must sprinkle the water of purifying upon them. This signifies the application of the blood of Christ to our souls by faith, that we may be fit to serve the living God. God declares his acceptance of them. All who expect to share in the privileges of the tabernacle, must resolve to do the service of the tabernacle. As, on the one hand, none of God's creatures are his necessary servants, he needs not the service of any of them; so none are merely honorary servants, to do nothing. All whom God owns, he employs; angels themselves have their services.