Exodus 13:9

13:9 It will be a sign for you on your hand and a memorial on your forehead, so that the law of the Lord may be in your mouth, for with a mighty hand the Lord brought you out of Egypt.

Exodus 13:14

13:14 In the future, when your son asks you ‘What is this?’ you are to tell him, ‘With a mighty hand the Lord brought us out from Egypt, from the land of slavery.