Exodus 16:32-34

32Then Moses said, “This is the word which the Lord commands, ‘Let an omer of it be kept throughout your generations, that they may see the bread with which I fed you in the wilderness, when I brought you out of the land of Egypt.’ ”

33So Moses said to Aaron, “Take a pot and put an omer of manna in it, and place it before the Lord to be kept throughout your generations.”

34As the Lord commanded Moses, so Aaron [eventually] placed it in the presence of the Testimony, to be kept.