Which Came First?

I find it fascinating that Exodus 12 comes before Exodus 14.

Now, for everybody who learned to count in kindergarten, you're looking at those numbers and thinking, "That is one dumb thing to find fascinating."

But look at what's happening in the story.
Exodus 10:  The 8th and 9th plagues (locusts and darkness).
Exodus 11:  God announces the 10th plague on its way.  Moses and Aaron go tell Pharaoh.
Exodus 12, part 1:  God institutes the Passover celebration.  He gives them the rites and rubrics.  He lays it all out, how they are to celebrate this festival for the rest of forever.
Exodus 12, part 2:  The 10th plague.  And the Israelites hustling out of Egypt.
Exodus 13, part 1:  More about the liturgy of Passover and also about the redemption of the firstborn.
Exodus 13, part 2:  Traveling from Goshen to the Red Sea.
Exodus 14:  The Lord's deliverance of His people.
Exodus 15:  The song of praise about the deliverance.

You would think that God would rescue His people FIRST.  And then they'd respond.  You'd think the event itself would precede the instructions of how they were to celebrate/remember the event.  But no.  God does it backward from our way of looking at it.  First comes the WORD which tells them how to celebrate what He hadn't even done yet. 

It's almost like His word makes things happen or somethin'.

It's like God thinks the liturgy to celebrate/remember these events is as important as the event itself.  (If I brought this up in Bible class, this is where my pastor would probably point out Luke 24: 46-47 where Jesus says that it was necessary for the Christ to suffer/die/rise AND necessary that it be preached.)