High Priest Garments Atone
The positioning of the holy garments of the Kohanim, to the sacrifices, was to teach that just as קרבנות atone for sins, so, too, do the בגדי כהונה, the priestly garments.
Each of the eight items worn by the Kohein Hagadol, were meant for a specific sin. This is all based on the Talmud in מסכת זבחים.
The כתונת, or robe, was to atone for bloodshed, as was hinted to when Yosef’s brothers dipped his כתונת פסים, coat of many colors was dipped in blood. The מכנסי בד, or pants, were to atone for sins related to forbidden sexual behavior. The מצנפת, or hat, atoned for haughtiness and arrogance. The אבנט was a kind of belt, or girdle. It was to atone for הרהור הלב, bad, sinful thoughts. The חושן, or breastplate, atoned for דינים, harsh judgement. The אפוד, which was a kind of apron, atoned for עבודה זרה, idol worship. The מעיל, was another type of apron that atoned for evil speech, לשון הרע. And the ציץ, the headband that said, קודש לה׳, atoned for brazenness.
It was said that brazen individuals with no shame, would be changed dramatically, just by looking at the ציץ. It is understandable that Alexander the Great was moved so greatly, just by seeing Shimon Hatzaddik in his eight priestly garments. It motivated him to treat the Jews well, and be admired by Jews for generations.
This is why so many Jews still use the name Alexander to this very day.