Exodus 9:18

9:18 I am going to cause very severe hail to rain down about this time tomorrow, such hail as has never occurred in Egypt from the day it was founded until now.

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.