They said to him, “Then what sign will you perform, so that we may see it and believe you? What work will you do?
In context
28They said to him, “What must we do to carry out the works of God?” 29Jesus answered them, “This is the work of God: to believe in the one he has sent.” 30They said to him, “Then what sign will you perform, so that we may see it and believe you? What work will you do? 31Our ancestors ate the manna in the desert; as it is written, ‘He gave them bread from heaven to eat.’” 32Jesus said to them, “Very truly I tell you, it was not Moses who gave you the bread from heaven; it is my Father who gives you the true bread from heaven.