Israel was separated from God. There was only one way into his presence. Exodus 27:16 After entering through the Door, the first order of business is the bronze altar, where a Lamb bears the penalty of their sin. To enter the Holy place, they must be of the tribe of Levi, set apart unto God, and must be washed in the bronze laver. In the same way today, those who are holy and sanctified may enter the holy place: bought by the Blood of the Lamb, and cleansed by the washing of the Word - the perfect law of liberty which like the mirrors from which the laver was made, reveals to us our sin.
Within the holy place, the Levites ate and drank at the Lord's table, offered the prayers of the people at the altar of incense, and kept the lamps burning on the lampstands. They were separated from the awe filled presence of God by a veil. In the same way, the churches of God are a light unto the world, and the veil in the temple has been torn asunder, so that we may approach the mercy seat.