Exodus 16:4-6

4Then the Lord said to Moses, “Behold, I will cause bread to rain from heaven for you; the people shall go out and gather a day’s portion every day, so that I may test them [to determine] whether or not they will walk [obediently] in My instruction (law).

5And it shall be that on the sixth day, they shall prepare to bring in twice as much as they gather daily [so that they will not need to gather on the seventh day].”

6So Moses and Aaron said to all Israel, “At evening you shall know that the Lord has brought you out of the land of Egypt,