Numbers 9:1-5

1In the first month of the second year after their departure from the land of Egypt, the Lord told Moses in the Wilderness of Sinai,

2“The Israelites are to observe the Passover at its appointed time.

3You must observe it at its appointed time on the fourteenth day of this month at twilight; you are to observe it according to all its statutes and ordinances.”

4So Moses told the Israelites to observe the Passover,

5and they observed it in the first month on the fourteenth day at twilight in the Wilderness of Sinai. The Israelites did everything as the Lord had commanded Moses.