In Leviticus 16, Aaron performs the biblical Yom Kippur Temple ritual.
Aaron, Moses’ brother and the first High Priest of Israel, is instructed to enter the sanctuary on the Day of Atonement. The ritual involved special sacrifices, purification, incense, and entry into the Holy of Holies, the innermost sanctuary. A central element was the use of two goats: one was sacrificed, while the other was symbolically sent away into the wilderness, giving rise to the term “scapegoat.”
Leviticus presents Aaron as the figure who performs the inaugural ritual, but later Yom Kippur services were carried out by successive High Priests. The ceremony could occur only once a year, making it the most restricted and solemn Temple service. After the destruction of the Second Temple in 70 CE, Jewish observance shifted from sacrifices to prayer, fasting, confession, and repentance.
The question’s wording can cause a minor confusion: Moses receives or conveys divine instructions in the Torah, but Aaron is the priest who performs the ritual. Ezra and Samuel were important biblical figures, yet neither is the priest named in Leviticus 16 for this service.