And thou shalt make a plate of pure gold, and grave upon it, like the engravings of a signet, HOLINESS TO THE LORD. And thou shalt put it on a blue lace, that it may be upon the mitre; upon the forefront of the mitre it shall be. And it shall be upon Aaron's forehead, that Aaron may bear the iniquity of the holy things, which the children of Israel shall hallow in all their holy gifts; and it shall be always upon his forehead, that they may be accepted before the LORD. (Ex 28:36-38)
There is an unusual word in this passage. At least many of us would not expect this word in this context; and yet there it is. Aaron was to bear the “iniquity of the holy things.” How are we to interpret this? If the things are holy, how can they have any iniquity or guilt? And if guilt, why should Aaron be the one to bear it? And how would wearing a gold plate on his hat (turban) indicate this iniquity?
The Hebrew word used here is avon, from a root word, avah, which means to twist or distort. Thus iniquity or guilt results from a distortion or twisting of God’s word. (Peter expressed the same idea in Greek when he spoke of those who “wrest” scriptures, “to their own judgement.” (2 Pet 3:16)) The word is not to be confused with avad (work), from which is derived the Hebrew word avodah, which is worship. Nevertheless, Aaron’s bearing the avon was part of the avodah.
Generally when we think of something as a holy thing we don’t associate it with iniquity or guilt. After all, isn’t a definition of holiness a state of being guiltless? Consider, though, the nature of the holy things in question—the Tabernacle and the offerings. There is an interpretation that says if it had not been for the incident of the golden calf there would not have been a Tabernacle. If the Israelites had not so quickly violated the Ten Commandments, God would have dwelt with them directly; because they sinned he needed a separation from them. The reason for most offerings, especially the sin offerings, was to take away the guilt of the sins of the people. Thus the holy things were as a result of iniquity; so when Aaron wore the holy garments he was bearing the iniquity that created the necessity for the holy things.
Even so, one would think that the iniquity would then be associated with the tent and the altar. But the word is used in the context of the gold plate upon the High Priest’s turban. For whom was that plate a reminder of holiness? It was not likely for the people, because most of the people would rarely see Aaron in his garments. They would deal mostly with the other priests. It might have been a reminder to God, but God is the one who actually imparted the holiness. Possibly it was a reminder to Aaron, himself. As he put on the garments of the High Priest he would see this reminder that he represented holiness to the Lord. Particularly in the fall, he was the only one who could atone for the people. In reminding him of his responsibility, the diadem also calls attention to the iniquity of his people. So in bearing the gold plate on his head, the High Priest actually bears the iniquity which causes the holy things.
The third question was, why Aaron? There is a whole branch of Christian theology that deals with types and antitypes. While we normally (typically) think of typical meaning routine, Typological Theology looks at things or events (usually in the Old Testament) as typical of (picturing) Jesus or the church. In this way of thinking, Aaron bears the iniquity of the holy (the word “things” being supplied by the translators for ease of understanding or misunderstanding) while Jesus bears the iniquity of the holy people. This is the main argument of Hebrews 9. The High Priest of the Tabernacle represents the Messiah who now has come to bear the sins of all people who will follow him. Aaron and his heirs represented a holy people to God. All of the guilt of the people was actually placed on the High Priest. In like manner, all the guilt and sin of those who choose to be God’s people rested on Jesus, and was eternally removed in his death on the tree. Because he bore the iniquity of the holy, we are the holy.