The same came to him by night, and said to him, "Rabbi, we know that you are a teacher come from God, for no one can do these signs that you do, unless God is with him."

 John begins by asserting the supremacy of Jesus. If we want information, we have to go to the person who possesses that information. If we want information about a family, we will get it at first hand only from a member of that family. If we want information about a town we will get it at first hand only from someone who comes from that town. So, then, if we want information about God, we will get it only from the Son of God; and if we want information about heaven and heaven's life, we will get it only from him who comes from heaven. When Jesus speaks about God and about the heavenly things, says John, it is no carried story, no second-hand tale, no information from a secondary source; he tells us that which he himself has seen and heard. To put it very simply, because Jesus alone knows God, he alone can give us the facts about God, and these facts are the gospel. 