Masechet Yoma describes the events leading up to Yom Kippur and the events of Yom Kippur itself, the holiest day in the Jewish calendar and in the Temple service. The Masechet opens with the sequestering of the Kohen Gadol (High Priest) 7 days before Yom Kippur. We will learn why this was done and the biblical source for it. We will learn about the receiving of the Torah and the events that led up to it, including the cloud that covered the mountain. We will then learn about the concept of impurity being permitted or suspended in communal offerings.