Numbers 2:34

2:34 So the Israelites did according to all that the Lord commanded Moses; that is the way they camped under their standards, and that is the way they traveled, each with his clan and family.

Numbers 9:5

9:5 And they observed the Passover on the fourteenth day of the first month at twilight in the wilderness of Sinai; in accordance with all that the Lord had commanded Moses, so the Israelites did.