Arcana Coelestia#9739
9739. 'As it has appeared to you on the mountain, so they shall make [it]' means in keeping with the correspondence of Divine realities in heaven. This is clear from the meaning of the altar that 'appeared on the mountain' as an outward form corresponding to Divine realities in heaven. For Mount Sinai means heaven, 8805, 9420, and the outward forms that appear in heaven correspond completely to actual Divine celestial and Divine spiritual realities, which belong to goodness and truth. The fact that these realities are presented in this visual way to the inner sight of angels and spirits may be recognized from all that has been stated and shown previously regarding the representation of heavenly realities within natural forms, in 1619, 1971, 1980, 1981, 2987-3003, 3213-3227, 3475, 3485, 6319, 9457, 9481, 9574, 9576, 9577. The Divine realities to which the altar corresponded are the ones that have been described up to now.
Arcana Coelestia#2987
2987. REPRESENTATIONS AND CORRESPONDENCES
Few are aware of what representations and of what correspondences are. Nor can anyone know what they are unless he knows that there is a spiritual world and that this is distinct and separate from the natural world. For between spiritual things and natural things correspondences exist, and the manifestations of spiritual things within natural are representations. They are called correspondences because they correspond, and representations because they represent.