Jewish 8 day pilgrimage festival celebrating the Exodus from slavery to freedom. Also known as Passover.
"And this day shall become a memorial for you, and you shall observe it as a festival for the L-RD, for your generations, as an eternal decree shall you observe it. For seven days you shall eat unleavened bread, but on the first day you shall remove the leaven from your homes ... you shall guard the unleavened bread, because on this very day I will take you out of the land of Egypt; you shall observe this day for your generations as an eternal decree." - Exodus 12:14-17