God knows us. He knows we tend to forget. So he helps us remember.
Exodus 12:25-27 (NLT)
When you enter the land the Lord has promised to give you, you will continue to observe this ceremony. Then your children will ask, “What does this ceremony mean?’ And you will reply, ‘It is the Passover sacrifice to the Lord, for he passed over the houses of the Israelites in Egypt. And though he struck the Egyptians, he spared our families.”
God provided ceremonies, traditions and memorials as reminders. Like the Passover celebration. 
