Exodus 16:12-16

“I have heard the grumblings of the sons of Israel; speak to them, saying, ‘At twilight you shall eat meat, and in the morning you shall be filled with bread; and you shall know that I am the LORD your God.’ ” So it came about at evening that the quails came up and covered the camp, and in the morning there was a layer of dew around the camp. When the layer of dew evaporated, behold, on the surface of the wilderness there was a fine flake-like thing, fine as the frost on the ground. When the sons of Israel saw it, they said to one another, “What is it?” For they did not know what it was. And Moses said to them, “It is the bread which the LORD has given you to eat. This is what the LORD has commanded, ‘Gather of it every man as much as he should eat; you shall take an omer apiece according to the number of persons each of you has in his tent.’ ”