Exodus 16:14-20

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.’ ” The sons of Israel did so, and some gathered much and some little. When they measured it with an omer, he who had gathered much had no excess, and he who had gathered little had no lack; every man gathered as much as he should eat. Moses said to them, “Let no man leave any of it until morning.” But they did not listen to Moses, and some left part of it until morning, and it bred worms and became foul; and Moses was angry with them.