Passover

Wednesday was passover, a time to celebrate God's miraculous deliverance from Egypt. Pharoah would not let the people of Israel go, and even after nine plagues, he stubbornly refused to let them go. Only after the tenth plague would pharoah relent. The tenth plague was the death of the firstborn.
Moses instructed the people of Israel what to do: The passover lamb was slaughtered and its blood was brushed onto the doorposts of the house. The people were to roast the lamb and serve it with unleavened bread and bitter herbs. The angel of the Lord passed over the homes marked with the lamb's blood, and smote the firstborn of every other houshold.
There was mourning over all of Egypt. Pharoah finally let the people go, but he changed his mind, and sent his army after them. This is what Moses said, after God rescued them by parting the Red Sea:
"Who is like to you among the gods, O Lord?
Who is like to you, magnificent in holiness?
O terrible of renown, worker of wonders,
when you stretched out your right hand,
the earth swallowed them!
In your mercy you led the people you redeemed;
in your strength you guided them
to your holy dwelling."
Genesis 15: 11-13