The Gospels are each unique. That’s one of the big takeaways I had from seminary. Matthew, Mark, Luke, and John all had one goal: tell the gospel of Jesus. That said, they went about that goal in different ways, working with overlapping material, as well as different material, with editorial work that reflects their different audiences and short-term purposes (which scholar debate about endlessly so I won’t even try to wade into that right now.)

All that said, John’s bit more unique. The other three are typically known as the synoptic Gospels because they all share a ton of material, and seem to follow a similar timeline with expanded sections here and there. John kinda does his own thing. He’s got these long expanded meditations, speeches, and limited action. He’s like the odd kid in the corner staring at bark, wondering what it’s made of, when the other three are out on basketball court running about.

Calvin tries to capture this difference in his opening to the commentary on John:

Yet there is also this difference between them, that the other three are more copious in their narrative of the life and death of Christ, but John dwells more largely on the doctrine by which the office of Christ, together with the power of his death and resurrection, is unfolded. They do not, indeed, omit to mention that Christ came to bring salvation to the world, to atone for the sins of the world by the sacrifice of his death, and, in short, to perform every thing that was required from the Mediator, (as John also devotes a portion of his work to historical details;) but the doctrine, which points out to us the power and benefit of the coming of Christ, is far more clearly exhibited by him than by the rest. And as all of them had the same object in view, to point out Christ, the three former exhibit his body, if we may be permitted to use the expression, but John exhibits his soul. On this account, I am accustomed to say that this Gospel is a key to open the door for understanding the rest; for whoever shall understand the power of Christ, as it is here strikingly portrayed, will afterwards read with advantage what the others relate about the Redeemer who was manifested.

–Commentary on John, Preface

While recent literary theory and technique have shown the way that the other Gospel-writers were still doing some deep, meditative theology in their Gospels, there’s something special about dwelling at length on John’s account. As Calvin hints, staring deep into the eyes of Jesus in John, helps you understand his acts and words in the other Gospels.

In other words, spend some time with the odd kid in the corner. Just like in real life, this can pay off.

Soli Deo Gloria

There are so many awesome resources on John, but here are two I’ve found beneficial:
John for Everyone Part 1 Part 2 by N.T. Wright – While he’s got some quirky takes here and there, Wright does a beautiful job grounding John’s unique Gospel in 1st Century history, unlike some others, and keeps it quite readable.
The Gospel According to John by D.A. Carson – Scholarly enough, but very pastoral, Carson’s commentary is also well-rooted in history. Great for preaching and paper-writing.