John 6:29 in the King James Version
Jesus answered and said unto them, This is the work of God, that ye believe on him whom he hath sent.
Context
28 They said therefore to him, “What must we do, that we may work the works of God?”
29 Jesus answered them, “This is the work of God, that you believe in him whom he has sent.”
30 They said therefore to him, “What then do you do for a sign, that we may see and believe you? What work do you do?