Exodus 16:15-16

So when the children 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, “This is the bread which the LORD has given you to eat. This is the thing which the LORD has commanded: ‘Let every man gather it according to each one’s need, one omer for each person, according to the number of persons; let every man take for those who are in his tent.’ ”