Aaron offered them for a wave offering. -
This is interesting and instructive. The Levites were substituted for the firstborn of Israel. They were first separated from the rest of the people, cleansed, sprinkled, shaven, and finally presented to the Lord by the act of Aaron, who, according to the Hebrew word, waved them before the Lord. This waving must, of course, have been done in symbol and figure. But it was not enough that they were thus waved, they had thereafter to go in to do their service. In other words, they were called to realize actually that which was their position and standing in the sight of God.
There is a precise analogy in all this to the work which the Lord Jesus has accomplished for us all. He said, "I consecrate Myself, that they also may be consecrated." When He offered Himself without spot to God, to do His Father's will, though it cost Him the agony of Calvary, the heavenly Aaron waved us before God to be His. We were separated by His most precious death, that we should be wholly for God. But what is ours in the great deed of Christ, must become ours by our own choice and deed. We must go in to do the service for which we have been chosen and set apart by the Holy Ghost.
This can only be through the grace of the blessed Spirit. Ask Him to realize in you the purposes of God: trust Him to keep you trusting: each morning say, "Holy Spirit, I rely on Thee to keep me in the current of the Divine purpose." Then dare to go forth to do the day's duties, believing that you may be always engaged in God's holy service; that in everything, whether you eat, or drink, or whatsoever you do, you do all to the glory of God.