Exodus 16:4-6

4Then the Lord said to Moses, “Look, I’m going to rain down food from heaven for you. Each day the people can go out and pick up as much food as they need for that day. I will test them in this to see whether or not they will follow my instructions.

5On the sixth day they will gather food, and when they prepare it, there will be twice as much as usual.”

6So Moses and Aaron said to all the people of Israel, “By evening you will realize it was the Lord who brought you out of the land of Egypt.