In the setting a part of the priest for service to God there are some basic principles which have some permanent significance. The ceremonies of washing, cleansing, anointing, and offering the special sacrifices were preformed to show that a priest could not lead others further in the service of God than he had gone himself. In order to serve God, one must be both clean and pure, as well as being set apart by God.
The washing away of all that was unclean was probably the forerunner of Christian baptism. The priesthood was to belong to the family of Aaron by a “perpetual statute.”
There were three types of animal sacrifices: a sin offering, a burnt offering, and a wave offering. The sin and burnt offerings had been used over the years by the Israelites but for persons other than priest. The final offering, though similar to other wave offerings in the Old Testament, was specifically designed as the offering of ordination.
Each offering had a separate meaning for the priest. The sin offering was to cleanse the priest of their sins. The burnt offering, which was wholly consumed, was symbolic of their total devotion to the will and service of God. The priest laid their hands on the heads of the animals to show they were identifying themselves with them. There are other symbols present with the wave offering of ordination. Blood was used in the sense of life and touching it to the ear, thumb, and toe showed that God had given special life to these organs. The priest was to hear and obey the voice of God, while his hands and feet were to be devoted to the divine service.
In the wave offering a portion of the animal was moved towards the altar and then away from it, rather than in a right to left motion. The symbolism here was that the offering was being given to God and then being given back to the priest by God. Throughout the history of Israel these portions were the payment to the priest. This was their “It shall be for Aaron and his sons as their portion forever from the sons of Israel.”
The seven day devoted to the ordination of the priest was probably quite literal, and it carried the idea that they were completely devoted to God. Seven days of ordination was also to signify that every day of the week was to be devoted to their service of God. During this ceremony, not only were the priest sanctified; the altar was also sanctified.
The laws concerning the daily sacrifices were next given. These later came to be the heart of the Hebrew sacrificial system. The purpose of these daily sacrifices was set forth as indicating that as Israel presented her sacrifices at the door of the “tent of meeting,” so God would meet with them and reveal his word to them.
As Moses, the priest, and the people were going through these symbolic motions, the actual consecration of both persons and objects was done by God. His grace made this effective. This purpose of this ritual and this consecration was that God “I will dwell among the sons of Israel.” Thiers was a ritual to help the Israelites to remember that is was their God who redeemed them from Egypt. The final phrase “I am the LORD their God” is uniquely a covenant phrase. The Israelites were His people through the Exodus and the covenant; they had a special ritual of worship.
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