The Gospel of John

 

This might be decades old now, but has stood the test of time. It is still unbeaten in it's depth and clarity. It provides great contextual details, guiding through the Jewish background. Brown captures the incredible richness of John's imagery wonderfully. I still consider this to have pride of place among John commentaries.

The whole book

I've only used Volume I of Brown's set, but I found it disappointing. He makes lots of helpful connections to related scripture passages, but spends too much time (in my opinion) discussing how likely it is that a certain story actually happened and how John may or may not be re-working synoptic material. Interesting, perhaps, but I wanted to hear more about John's text.

I always look to RE Brown first; it's getting old, but I've learned so much from him I start with his 2-volume commentary [Full Review]