Commentaria in Exodum
There is also this reason: that altar was made for burning incense before God; therefore it had to be placed within the Holy of Holies before the ark, where God above all showed his presence.
The contrary opinion, held by Beda, book 3 On the Tabernacle, chapters 11 and 12, by St. Thomas, 1–2, Question 102, article 4, reply to 6, by Lyranus, Abulensis, Cajetan, Lipomano, Ribera and others on Hebrews chapter 9, is that the altar of incense was outside the Holy of Holies, and that therefore the veil was between it and the Holy of Holies. This is the express opinion of Josephus, Antiquities book 3, chapter 7. It is proved first from this, that in chapter 30, verse 6, it is said: “Thou shalt set the altar over against the veil, which hangeth before the ark,” where the Hebrew has, before the veil, or in front of the veil, but not, within the veil.
Secondly, because in this chapter 40, verses 4 and 5, where the order of the tabernacle is described, it is said that Moses put the ark in the tabernacle, and hung the veil before it; then he put the table in the tabernacle, and the candlestick, and the altar of incense over against the veil: therefore this altar was not behind the veil, within the Holy of Holies, but in front, namely with the table and the candlestick.
Thirdly, because, as is said in chapter 30, verse 8, the priest had to burn incense daily on this altar; but the Holy of Holies could be entered only once a year: therefore this altar was not within the Holy of Holies. Whence Leviticus chapter 16, verse 18, speaking of the day of atonement (of which Moses also speaks in chapter 30, verse 10), when the priest, after entering the Holy of Holies, made atonement for the altar of incense, says: “And when he is come out (of the Holy of Holies) to the altar that is before the Lord;” therefore he had to go out from the Holy of Holies to the altar of incense: so this altar was not within the Holy of Holies.
Fourthly, only the high priest was permitted to enter the Holy of Holies; yet to the altar of incense the lesser priests also went in and laid on the incense, as is plain of Zachary, Luke chapter 1, who, being of the course of Abia, which was the eighth lot of the priests, 1 Paralipomenon chapter 24, in which course there was no high priest, went out by lot to offer the incense. For what some say, that the high priest entered the Holy of Holies once with the shedding of blood, but at other times often entered without it, plainly To the first I answer, that the Lord is not speaking of the incense that was burnt daily, but of the atonement for the altar of incense, which, as I said in the third argument, was atoned for by the priest once a year together with the whole tabernacle, after entering the Holy of Holies.
To the second I answer, that it is called the altar of the oracle because it was made for this purpose, that the incense might rise toward the oracle: whence also the veil, which was set between the Holy of Holies and the Holy Place, did not reach altogether from the floor to the roof, but at the top some part was left open, through which the smoke of the spices entered the oracle; although it may also be called the altar of the oracle because it was contiguous to the oracle, not far from it, as the altar of holocausts was; indeed this altar of incense corresponded plainly to the oracle, and was separated from it only by the veil; the Hebrew indicates this more clearly, which has, the altar at the oracle, which the Septuagint renders, the altar before the face of the oracle.
To the third, many interpreters, such as Anselm, will have it that the censer of which the Apostle speaks is that with which the high priest, entering the Holy of Holies, burnt incense; but St. Augustine and Origen, homily 9, here teach well that this censer was nothing other than the altar of incense, and Abulensis, Question 6, strongly confirms it; for besides the points which the argument put forward, if that censer of the high priest entering the Holy of Holies was in the Holy of Holies, then the high priest entered the Holy of Holies at least three times: first, to bring out the censer; secondly, when he returned with it filled with incense and fire, to burn the incense and to perfume the Holy of Holies; thirdly, when he had to go out again to put out the ashes and the fire, and to go back in to put back the censer; whereas he was permitted to enter the Holy of Holies only once, and that only with the censer and the incense; for otherwise the high priest who entered without these was to die, as is plain I answer therefore that this censer is the same as the altar of incense: nor is it strange that the altar is called a censer, because it was in the likeness of a great censer, and had no other use than a censer, namely to contain fire and incense. This is clearer in the Greek of Hebrews chapter 9, for there this censer is called by the very name by which Josephus names the altar of incense, Antiquities book 3, chapter 7, and Jewish War book 6, chapter 6; and if you look to its derivation, it means a place of perfuming: which can be understood of a censer properly so called as well as of an altar. With a like ending the altar is called a place of sacrifice.
To the argument I answer: when the Apostle says that the Holy of Holies had a golden censer, that is, the altar of incense, understand that it had it not within itself but outside the veil, set over against it, and erected for its worship and reverence: whence it is also called the altar of the oracle, as I said in the answer to the second. For there are various ways of having, says Aristotle in the Postpredicaments: thus a house has a court; a river has a bank; a temple has a tower, though not within itself: see Ribera, book On the Temple, chapter 7. This altar therefore stood before the veil, facing directly toward the mercy-seat, says Cajetan, and consequently was in the middle of the breadth of the tabernacle, so that the priest burning incense upon it and praying had his face directly toward the mercy-seat, the veil nevertheless coming between, that he might thus as it were turn himself toward God. See Villalpandus, page 344.
To the fourth I answer that this altar was erected for burning incense before God, but not by the blessed in heaven in the clear presence of God, who were signified by the Holy of Holies; but by the Church militant, which was signified by the Holy Place: for she knows, worships and adores God through the veil, in a mystery; whence this altar had to be set in the Holy Place, that is, in the Church militant, and not in the Holy of Holies, that is, in heaven.
31. AFTER ALL THINGS WERE PERFECTED, A CLOUD COVERED THE TABERNACLE OF THE TESTIMONY, AND THE GLORY OF THE LORD FILLED IT.—“The glory of the Lord” is the name given to that august cloud, which, although it was dense, was nevertheless bright and shining, and as it were veiled and signified the majesty of God. So St. Augustine, Question 173. Thus glory is often taken for light, brightness and splendour, as in Exodus chapter 24, verse 17, and chapter 33, verses 18 and 22; Leviticus chapter 9, verse 11; Ecclesiasticus chapter 45, verse 35; Ezechiel chapter 11, verse 4.
33. NEITHER COULD MOSES GO INTO THE COVERED PLACE OF THE COVENANT,—both out of reverence for the majesty of the Lord, says Cajetan, and because that dense cloud covered all things, so that Moses could not see.
A like thing happened at the dedication of the temple, 3 Kings chapter 8, verse 11. And this happened only the first time, when the tabernacle was dedicated; for at other times Moses went into it.
St. Augustine and Rabanus give an allegorical reason. For Moses bore the person of the Jews, to whom the glory of the Lord, which is in the tabernacle, that is, the grace of Christ which is in the Church, is set in the way like a cloud, so that they do not understand it, do not believe it, and therefore neither grasp it nor enter into it.