Summa Theologica I-II, q. 102: Of the Causes of the Ceremonial Precepts
But with regard to the figurative reason, the outward tabernacle, which was called the Holy Place, betokened the state of the Old Law, as the Apostle says (Heb. 9:6, seqq.): because into that tabernacle "the priests always entered accomplishing the offices of sacrifices." But the inner tabernacle, which was called the Holy of Holies, signified either the glory of heaven or the spiritual state of the New Law to come. To the latter state Christ brought us; and this was signified by the high-priest entering alone, once a year, into the Holy of Holies. The veil betokened the concealing of the spiritual sacrifices under the sacrifices of old. This veil was adorned with four colors: viz. that of linen, to designate purity of the flesh; purple, to denote the sufferings which the saints underwent for God; scarlet twice dyed, signifying the twofold love of God and our neighbor; and violet, in token of heavenly contemplation. With regard to the state of the Old Law the people and the priests were situated differently from one another. For the people saw the mere corporeal sacrifices which were offered in the court: whereas the priests were intent on the inner meaning of the sacrifices, because their faith in the mysteries of Christ was more explicit. Hence they entered into the outer tabernacle. This outer tabernacle was divided from the court by a veil; because some matters relating to the mystery of Christ were hidden from the people, while they were known to the priests: though they were not fully revealed to them, as they were subsequently in the New Testament (cf. Eph. 3:5).
Reply to Objection 5Worship towards the west was introduced in the Law to the exclusion of idolatry: because all the Gentiles, in reverence to the sun, worshipped towards the east; hence it is written (Ezech. 8:16) that certain men "had their backs towards the temple of the Lord, and their faces to the east, and they adored towards the rising of the sun." Accordingly, in order to prevent this, the tabernacle had the Holy of Holies to westward, that they might adore toward the west. A figurative reason may also be found in the fact that the whole state of the first tabernacle was ordained to foreshadow the death of Christ, which is signified by the west, according to Ps. 67:5: "Who ascendeth unto the west; the Lord is His name."
Reply to Objection 6Both literal and figurative reasons may be assigned for the things contained in the tabernacle. The literal reason is in connection with the divine worship. And because, as already observed (ad 4), the inner tabernacle, called the Holy of Holies, signified the higher world of spiritual substances, hence that tabernacle contained three things, viz. "the ark of the testament in which was a golden pot that had manna, and the rod of Aaron that had blossomed, and the tables" (Heb. 9:4) on which were written the ten commandments of the Law. Now the ark stood between two "cherubim" that looked one towards the other: and over the ark was a table, called the "propitiatory," raised above the wings of the cherubim, as though it were held up by them; and appearing, to the imagination, to be the very seat of God. For this reason it was called the "propitiatory," as though the people received propitiation thence at the prayers of the high-priest. And so it was held up, so to speak, by the cherubim, in obedience, as it were, to God: while the ark of the testament was like the foot-stool to Him that sat on the propitiatory. These three things denote three things in that higher world: namely, God Who is above all, and incomprehensible to any creature. Hence no likeness of Him was set up; to denote His invisibility. But there was something to represent his seat; since, to wit, the creature, which is beneath God, as the seat under the sitter, is comprehensible. Again in that higher world there are spiritual substances called angels. These are signified by the two cherubim, looking one towards the other, to show that they are at peace with one another, according to Job 25:2: "Who maketh peace in. . . high places." For this reason, too, there was more than one cherub, to betoken the multitude of heavenly spirits, and to prevent their receiving worship from those who had been commanded to worship but one God. Moreover there are, enclosed as it were in that spiritual world, the intelligible types of whatsoever takes place in this world, just as in every cause are enclosed the types of its effects, and in the craftsman the types of the works of his craft. This was betokened by the ark, which represented, by means of the three things it contained, the three things of greatest import in human affairs. These are wisdom, signified by the tables of the testament; the power of governing, betokened by the rod of Aaron; and life, betokened by the manna which was the means of sustenance.
Or else these three things signified the three Divine attributes, viz. wisdom, in the tables; power, in the rod; goodness, in the manna—both by reason of its sweetness, and because it was through the goodness of God that it was granted to man, wherefore it was preserved as a memorial of the Divine mercy. Again, these three things were represented in Isaias' vision. For he "saw the Lord sitting upon a throne high and elevated"; and the seraphim standing by; and that the house was filled with the glory of the Lord; wherefrom the seraphim cried out: "All the earth is full of His glory" (Is. 6:1, 3). And so the images of the seraphim were set up, not to be worshipped, for this was forbidden by the first commandment; but as a sign of their function, as stated above.
The outer tabernacle, which denotes this present world, also contained three things, viz. the "altar of incense," which was directly opposite the ark; the "table of proposition," with the twelve loaves of proposition on it, which stood on the northern side; and the "candlestick," which was placed towards the south. These three things seem to correspond to the three which were enclosed in the ark; and they represented the same things as the latter, but more clearly: because, in order that wise men, denoted by the priests entering the temple, might grasp the meaning of these types, it was necessary to express them more manifestly than they are in the Divine or angelic mind. Accordingly the candlestick betokened, as a sensible sign thereof, the wisdom which was expressed on the tables (of the Law) in intelligible words. The altar of incense signified the office of the priest, whose duty it was to bring the people to God: and this was signified also by the rod: because on that altar the sweet-smelling incense was burnt, signifying the holiness of the people acceptable to God: for it is written (Apoc. 8:3) that the smoke of the sweet-smelling spices signifies the "justifications of the saints" (cf. Apoc. 19:8). Moreover it was fitting that the dignity of the priesthood should be denoted, in the ark, by the rod, and, in the outer tabernacle, by the altar of incense: because the priest is the mediator between God and the people, governing the people by Divine power, denoted by the rod; and offering to God the fruit of His government, i.e. the holiness of the people, on the altar of incense, so to speak. The table signified the sustenance of life, just as the manna did: but the former, a more general and a coarser kind of nourishment; the latter, a sweeter and more delicate. Again, the candlestick was fittingly placed on the southern side, while the table was placed to the north: because the south is the right-hand side of the world, while the north is the left-hand side, as stated in De Coelo et Mundo ii; and wisdom, like other spiritual goods, belongs to the right hand, while temporal nourishment belongs on the left, according to Prov. 3:16: "In her left hand (are) riches and glory." And the priestly power is midway between temporal goods and spiritual wisdom; because thereby both spiritual wisdom and temporal goods are dispensed.