26 Jesus answered them and said, “Truly, truly, I say to you, you seek Me, not because you saw signs, but because you ate of the loaves and were filled. 27 Do not work for the food which perishes, but for the food which endures to eternal life, which the Son of Man will give to you, for on Him the Father, God, has set His seal.” 28 Therefore they said to Him,
“What shall we do, so that we may work the works of God?” 29 Jesus answered and said to them,
“This is the work of God, that you believe in Him whom He has sent.” 30 So they said to Him,
“What then do You do for a sign, so that we may see, and believe You? What work do You perform? 31 Our fathers ate the manna in the wilderness; as it is written, ‘He gave them bread out of heaven to eat.’” 32 Jesus then said to them, “Truly, truly, I say to you, it is not Moses who has given you the bread out of heaven, but it is My Father who gives you the true bread out of heaven. 33 For the bread of God is [
i]that which comes down out of heaven, and gives life to the world.” 34 Then they said to Him, “Lord, always give us this bread.”
The listeners may not have understood what "the work of God" meant, but they understood it was not their "work" to believe on [trust in] Jesus. The understood it as a sign from God that would make them believe.
What then do You do for a sign, so that we may see, and believe you
. What work do YOU perform [so that we may see and believe]?
The listeners right there knew "This is the work of God, that you believe in Him whom He has sent" was a work of God, not a work required by God. And if you don't believe that, then you believe
faith is a work required by God, which contradicts the rest of the New Testament.