WOW ! Aaron , Moses brother, was High Priest and he sinned . Aaron's death is remarkable ; the only person in scripture where his age (123) , day of death (1st day) and month of death (5th month- Av) and place of death (Mt Hor) are recorded. Numbers 33:38.
Upon Aaron's death, his son Eleazar became high priest. Exodus 29:30 states that upon Aaron's death his son shall put Aaron's garments on for 7 days and then enter the tabernacle. So Aaron dies on 1 Av and Eleazar enters the Tabernacle on 9 Av as High Priest........ !!!! This is the day , the Feast of New Wine.....
I sort of think it is next year , but I hope I am wrong...............