Exodus 16:3-4

And the sons of Israel said to them: "If only we had died by the hand of the Lord in the land of Egypt, when we sat around bowls of meat and ate bread until filled. Why have you led us away, into this desert, so that you might kill the entire multitude with famine?" Then the Lord said to Moses: "Behold, I will rain down bread from heaven for you. Let the people go out and collect what is sufficient for each day, so that I may test them, as to whether or not they will walk in my law.