Numbers 9
3 Ref In the fourteenth day of this month, at evening, you are to keep it at the regular time, and in the way ordered in the law.
4 And Moses gave orders to the children of Israel to keep the Passover.
5 Ref So they kept the Passover in the first month, on the fourteenth day of the month, at evening, in the waste land of Sinai: as the Lord gave orders to Moses, so the children of Israel did.