Exodus 16:15-16

15And when the children of Israel saw it, they said one to another, It is manna: for they wist not what it was. And Moses said unto them, This is the bread which the Lord hath given you to eat.1

16This is the thing which the Lord hath commanded, Gather of it every man according to his eating, an omer for every man, according to the number of your persons; take ye every man for them which are in his tents.23