The biblical month of Aviv, later renamed Nisan, begins at sundown this evening. God identified this month as the first month of the year when he gave instructions to Moses pertaining to the Passover and the exodus of the Israelites out of Egypt. (Exodus 12:2) The Jewish calendar is based on the phases of the moon with every month beginning on the day the first sliver of the moon appears following the dark moon. Every day begins at sundown and ends