The Ablution.
Unto the door of the tabernacle. The great laver was to be placed between the entrance to the tabernacle and the altar of burnt-offering (Exodus 30:18). It was to this probably that Aaron and his sons were to be brought. Its main purpose was to be a lustral vessel, placed ready for the various ablutions which the law required (Exodus 30:19-21). Thou …. shalt wash them with water. Ablutions were an important part of the ceremonial of almost all ancient religions. In Egypt, the priests were compelled to wash themselves from head to foot in cold water twice every day, and twice every night (Herod. 2.37). In the religion of Zoroaster frequent washing with water was prescribed for many kinds of impurity. The Greeks were particularly addicted to ceremonies of which ablution formed a part; and it is to Rome that we are indebted both for the word and for the idea of "lustration." It is a true instinct which has taught men the analogy between physical and moral purity, and led them to typify the removal of spiritual, by the cleansing from physical, defilement. The religion given at Sinai set a stamp of approval in many points on what may be called "the religion of nature;" and among them on this. Ablutions were required of the priests, not only at consecration, but every time that they entered the tabernacle, or sacrificed on the altar of burnt-offering (Exodus 30:20). Washing was a main feature in the cleansing of leprosy (Le 13:54, 58) and of the leper. (Le Exodus 14:8). It was also employed for the purification of many minor defilements (Le 11:25; Exodus 15:5; Exodus 17:15, etc.). At what date it first came into use in the admission of proselytes is uncertain. Whether the washing of consecration extended to the whole body, or was limited to the hands and feet, is also a point on which critics have disagreed, but one of no great importance. (See John 13:9, John 13:10.)
The Investiture of Aaron.