30:1-10 The altar of incense represented the Son of God in his human nature, and the incense burned thereon typified his pleading for his people. The continual intercession of Christ was represented by the daily burning of incense thereon, morning and evening. Once every year the blood of the atonement was to be applied to it, denoting that the intercession of Christ has all its virtue from his sufferings on earth, and that we need no other sacrifice or intercessor but Christ alone.

8. Aaron shall burn incense—seemingly limiting the privilege of officiating at the altar of incense to the high priest alone, and there is no doubt that he and his successors exclusively attended this altar on the great religious festivals. But "Aaron" is frequently used for the whole priestly order, and in later times, any of the priests might have officiated at this altar in rotation (Lu 1:9).