What is in John that someone might think it was the most Jewish?

It is often said that John is the Gospel to the world (and Matthew to the Jews, Mark to the Romans, and Luke to the Greeks). But some Jewish scholars think that John is the most Jewish of the Gospels. What is in John that someone might think it was the most Jewish? State at least three ways that support this view. Once you do this, if you disagree, state three reasons why you disagree.