The night before their forbears had left Egypt, they had a passover. Now, they once again keep the passover. They have gone from passover to manna to once more passover. They now will be fed by the crops of their new home.
Captive to Egypt, wandering in wilderness, celebration of freedom. Useful metaphors for us on our own journey from where we've been captive to worldly demands--or just our own selfish pleasures--to a period of lent, towards a new life--Eastertide, with its promises, rewards, and renewals.
Warning, though--they are in the land but haven't quite conquered it. Battles will occur. So for us when we make it through Lent to Easter. We'll still have some of those old temptations to face.