The Book of Jubilees claims to present "the history of the division of the days of the Law, of the events of the years, the year-weeks, and the jubilees of the world" as revealed to Moses (in addition to the Torah or "Instruction") by angels while he was on Mount Sinai for forty days and forty nights. The chronology given in Jubilees is based on multiples of seven; the jubilees are periods of 49 years (seven "year-weeks"), into which all of time has been divided.