This section is most interesting in that it tells who can and can't serve as priests, and what causes a temporary uncleanness. With this 7 Feasts are mentioned:
The first three feasts, Passover, Unleavened Bread and First Fruits fall in March and April.
The fourth one, Shavu'ot (Weeks or Pentecost), marked the summer harvest and occurs in late May or early June.
The last three feasts, Trumpets, Yom Kippur and Sukkot happen in September and October.
