Exodus 16:17

13 That evening quail came and covered the camp, and in the morning there was a layer of dew around the camp.

14 When the layer of dew had evaporated, there were thin flakes on the desert floor, as fine as frost on the ground.

15 When the Israelites saw it, they asked one another, “What is it?” For they did not know what it was. So Moses told them, “It is the bread that the LORD has given you to eat.

16 This is what the LORD has commanded: ‘Each one is to gather as much as he needs. You may take an omer for each person in your tent.’”

17 So the Israelites did this. Some gathered more, and some less.

18 When they measured it by the omer, he who gathered much had no excess, and he who gathered little had no shortfall. Each one gathered as much as he needed to eat.

19 Then Moses said to them, “No one may keep any of it until morning.”

20 But they did not listen to Moses; some people left part of it until morning, and it became infested with maggots and began to smell. So Moses was angry with them.

21 Every morning each one gathered as much as was needed, and when the sun grew hot, it melted away.

Read all of Exodus 16