"So they said to him (Jesus), 'What sign are you going to give us then so that we may see it and believe you? What work are you performing? Our ancestors ate the manna in the wilderness; as it is written, 'He gave them bread from heaven to eat.' Then Jesus said to them, 'Very truly, I tell you, it was not Moses who gave you the bread from heaven, but it is my Father who gives you the true bread from heaven. For the bread of God is that which comes down from heaven and gives life to the world.'"
John 6:30-33 (NRSV)