Among the many things the Book of Jubilees is concerned with, Passover receives special attention. According to Jubilees, the exact date of Passover — and the precise calendar by which it's calculated — was established by divine revelation to Abraham, renewed with Moses on Sinai, and has been mishandled by subsequent generations who adopted the lunar calendar.
Jubilees' account of the first Passover frames it as a renewal of something that already existed. When God told Moses to observe Passover on the 14th of the first month, he was restoring an observance that Abraham had already kept — the Feast of Passover — which Abraham himself had received as a divine command.
The calendar implications are significant. Jubilees insists on a solar calendar of 364 days, in which every feast day falls on the same day of the week every year. On this calendar, Passover always falls on a Wednesday. The Last Supper, the crucifixion, and the resurrection all happened on specific days in relation to Passover — and scholars have noted that if Jesus was using the solar calendar of Jubilees, the chronological puzzles in the Gospel accounts resolve in interesting ways.
John's Gospel, which places the crucifixion on the day the Passover lambs were being slaughtered (a day earlier than the Synoptic Gospels suggest), has been explained by some scholars as reflecting the mainstream lunar Passover, while the Synoptic Gospels reflect the solar calendar of Jubilees. Jesus, on this reading, celebrated Passover on Tuesday evening using the Jubilees calendar.
Whether this interpretation is right, the Book of Jubilees raises real questions about how the sacred calendar was intended to work — questions that scholars are still debating today.