Exodus 12:14
And this day will be a memorial for you, and you are to celebrate it as a feast to the LORD, as a lasting ordinance for the generations to come.

Exodus 12:17
So you are to observe the Feast of Unleavened Bread, for on this very day I brought your divisions out of the land of Egypt. You must observe this day as a lasting ordinance for the generations to come.

Exodus 12:25
When you enter the land that the LORD will give you as He promised, you are to observe this service.

Exodus 13:5
And when the LORD brings you into the land of the Canaanites, Hittites, Amorites, Hivites, and Jebusites--the land He swore to your fathers that He would give you, a land flowing with milk and honey--you shall keep this service in this month.

Exodus 13:10
Therefore you shall keep this ordinance at the appointed time year after year.