Deuteronomy 8:14-16

8:14 be sure you do not feel self-important and forget the Lord your God who brought you from the land of Egypt, the place of slavery, 8:15 and who brought you through the great, fearful desert of venomous serpents and scorpions, an arid place with no water. He made water flow from a flint rock and 8:16 fed you in the desert with manna (which your ancestors had never before known) so that he might by humbling you test you and eventually bring good to you.