John 6:28-31

²⁸Then they said to him, “What must we do, so that we may do the works of God?”

²⁹Jesus replied and said to them, “This is the work of God: That you believe in the one whom he has sent.”

³⁰So they said to him, “What sign then will you do, so that we may see and believe you? What will you do?

³¹Our fathers ate the manna in the wilderness, as it is written, 'He gave them bread from heaven to eat.'”