Merely being constrained by love or acknowledging His legal right does not constitute consecration. After a person has been constrained by the Lord’s love and has acknowledged His right, there is a further step that he should take. This step will bring him on to a new position. Through the Lord’s constraining and based on His purchase, we separate ourselves from every other thing. Henceforth, we live for and unto the Lord. This is consecration. In some instances in the Old Testament, the Chinese Union Version translates the word consecration as "the receiving of the holy service." To receive the holy service is to receive the ministry of service to God. This is a holy service. This is consecration. Consecration is receiving the ministry of serving God. It is to say to the Lord, "Today I will separate myself from everything to serve You, because You have loved me."
Let us look at Exodus 28:1-2 and 29:1, 4, 9-10.
After reading these verses, we can see that consecration is a very special matter. The nation of Israel was a nation chosen by God (Exo. 19:5-6), but it did not become a consecrated nation. There were twelve tribes among the Israelites, but not all the twelve tribes received the holy service. The tribe of Levi was one of the twelve tribes. They were a tribe chosen by God (Num. 3:11-13), but they were not a consecrated tribe. Among the many Levites, only the household of Aaron received the holy service. Not all of the Israelites received the holy service, not even all of the Levites. Only the household of Aaron received the holy service. In order to be consecrated, one had to belong to this household. If one were not a member of this household, he could not consecrate himself. Only the members of this household—the household of Aaron—were qualified to be priests, and only they could consecrate themselves.
Thank God, today we are the members of this household. Those who believe in the Lord are the members of this household. All who have been saved by grace are priests (Rev. 1:5-6). God has chosen us to be the priests. Initially, only the members of Aaron’s household could consecrate themselves; if anyone else came near, he would have been put to death (Num. 18:7). We must remember that only those chosen by God to be priests can consecrate themselves. Thus, only the members of this household could consecrate themselves. Today God has chosen us to be the priests; therefore, we are the members of this household. Hence, we are qualified to consecrate ourselves.
Here we see that man does not consecrate himself because he has chosen God. Rather, God is the One who chooses and calls, and then man consecrates himself to Him. Those who consider that they are doing God a favor by forsaking all are but outsiders; they are not consecrated at all. We must realize that our service to God is not a favor or courtesy to God. It is not a matter of offering ourselves to God’s work, but a matter of God being gracious to us and giving us a portion of His work. It is God who has given us the glory and the beauty. The Bible tells us that the holy garment of the priest is for glory and beauty (Exo. 28:2). Consecration is God giving us glory and beauty; it is God calling us into His service. If we boast in anything at all, we must boast in our marvelous Lord. There is nothing marvelous for the Lord to have servants like us. The marvelous thing is for us to have such a Lord! We must see that consecration is the result of being chosen. Serving God is an honor to us. We are not uplifting God, as if we were sacrificing anything for Him or as if we had any glory in ourselves. Consecration is God giving us the glory. We should prostrate ourselves before Him and say, "Thank You that I can have a part in Your service. There are so many people in this world, yet I am chosen to have a part in it!" Consecration is our honor, not our sacrifice. It is true that we need to have the greatest sacrifice, but there is no sense of sacrifice in consecration. There is only the full sense of God’s glory.
(New Believers Series: Consecration #7, Chapter 1, by Watchman Nee)