2. Mose 28:36

The fourth article of the high priest's dress was the diadem upon his head-band. ציץ, from צוּץ to shine, a plate of pure gold, on which the words ליהוה קדשׁ, "holiness (i.e., all holy) to Jehovah," were engraved, and which is called the "crown of holiness" in consequence, in Exo 39:30. This gold plate was to be placed upon a riband of dark-blue purple, or, as it is expressed in Exo 39:31, a riband of this kind was to be fastened to it, to attach it to the head-band, "upon the fore-front (as in Exo 26:9) of the head-band," from above (Exo 39:31); by which we are to understand that the gold plate was placed above the lower coil of the head-band and over Aaron's forehead. The word מצנפת, from צנף to twist or coil (Isa 22:18), is only applied to the head-band or turban of the high priest, which was made of simply byssus (Exo 28:39), and, judging from the etymology, was in the shape of a turban. This is all that can be determined with reference to its form. The diadem was the only thing about it that had any special significance. This was to be placed above (upon) Aaron's forehead, that he "might bear the iniquity of the holy things, which the children of Israel sanctified, with regard to all their holy gifts,...as an acceptableness for them before Jehovah." עון נשׁא: to bear iniquity (sin) and take it away; in other words, to exterminate it by taking it upon one's self. The high priest was exalted into an atoning mediator of the whole nation; and an atoning, sin-exterminating intercession was associated with his office. The qualification for this he received from the diadem upon his forehead with the inscription, "holiness to the Lord." Through this inscription, which was fastened upon his head-dress of brilliant white, the earthly reflection of holiness, he was crowned as…

Orders being given for the fitting up of the place of worship, in this and the following chapter care is taken about the priests that were to minister in this holy place, as the menial servants of the God of Israel. He hired servants, as a token of his purpose to reside among them. In this chapter, I. He pitches upon the persons who should be his servants (Exo 28:1). II. He appoints their livery; their work was holy, and so must their garments be, and unanswerable to the glory of the house which was now to be erected (Exo 28:2-5). 1. He appoints the garments of his head-servant, the high priest, which were very rich. (1.) An ephod and girdle, (Exo 28:6-14). (2.) A breast-plate of judgment (Exo 28:15-29), in which must be put the urim and thummim (Exo 28:30). (3.) The robe of the ephod (Exo 28:31-35). (4.) The mitre (Exo 28:36-39). 2. The garments of the inferior priests (Exo 28:40-43). And these also were shadows of good things to come.

28:36-38 Like all the other elements of the high priest’s clothing and activities, the medallion worn on the front of the turban was to remind the people that God is holy, and his holiness had implications for their entering his presence. God wished to dwell with his people, but his holiness would destroy them unless he took preventative steps. God determines the way into his presence; we do not. The central question of the Bible is how a sinful people can live in the presence of a holy God so that God can share his holy character with them. Ultimately, the answer is provided in Jesus Christ, the Holy One of God who is the perfect mediator (Luke 4:34; Heb 9:11-15). He did not die only to rescue us from the consequences of our sin, but so that God can live in us, reproducing his holy character in us (Eph 2:10; 4:22; Phil 1:27; 1 Pet 1:13-16).