 The old ark contained a jar of the manna, the miracle bread from heaven that fed the Israelites in the desert. Well, what does Mary contain in her body? It's a who, again, not a what. It is, of course, Jesus Christ, who is the living bread from heaven. If you read the wonderful Eucharistic discourse in John 6, when Jesus says, I am the bread of life, your fathers ate the manna in the wilderness, and yet they died.