Writing in the Evangelical Dictionary of Biblical Theology, John Oswalt says that, while it is possible to read too much into the detailed instructions for the construction of the tabernacle (in Exodus 25ff), the main points are clear enough.
Several colours are significant. White suggests the purity of God and the needed purity of his people. Blue indicates God’s transcendence; purple, his royalty, and red, the blood that must be shed if sinful humans are to approach a holy God.
The separation between God and sinner is suggested by the court itself, along with curtain at the door of the Holy Place, and the one which closed off the Holy of Holies.
The possibility of people coming into God’s presence is indicated by the first object encountered, the altar. This teaches that ‘without the shedding of blood there is no forgiveness of sins’ (Heb 9:22).
Then came the laver. Those who would come into the presence of a pure God must be made clean (cf. Psa 51:7).
Coming now to the Holy Place itself, we encounter on the right a table with twelve loaves of bread on it. This suggests, not as with pagan worship, a place where God himself eats, but rather indicates that God supplies his people with bread both physical and spiritual. On the left is a lampstand, whose light is never to be allowed to go out. God is light to his people in this world which is dark because of sin. Straight ahead is the altar of incense. The perpetual burning of incense symbolised both the presence of God and the prayers of the worshipers (Ps 141:2; Rev 8:3–4). ‘Thus,’ (concludes Oswalt) ‘the objects in the Holy Place were the evidence of the blessings that are for those who live in the presence of God: light, sustenance, and communion.’
In pagan temples, the innermost place was reserved for the idol itself. But, in the case of the tabernacle, this position is taken by the ark (quite simply, a ‘chest’, or ‘box’). This box emphatically does not contain an image of God. Rather, it functions more as God’s royal footstool. The two cherubim, with their outstretched wings, are situated at each end of the box. Inside the box are the two tablets of the Decalogue, a constant reminder of God’s lofty moral standards. The lid of the box (called the ‘mercy-seat’ in older translations) may be thought of as not only a physical but also a metaphorical ‘cover’ – a place where, once a year, sprinkled animal blood would ‘cover’ the sins of the people. ‘The broken covenant, calling out for the death of those who swore in the name of God that they would be obedient or die, was satisfied by a representative sacrificial death.’
All of this leaves the question: how could such an arrangement, with its sacrifice of bulls and goats, enable a holy God and his sinful people to be reconciled? The answer, of course, that it points forward to Christ. Everything ‘pointed to the One who could indeed die for all. If God could die and then return to life, that death could indeed be in the place of all who would ever live and sin.’
(Note: I believe that the above accurately summarises Oswalt’s main points, with the exception of the few words in italics, which represent a thought not included in his article)