The Gospel According to John by D.A. Carson is arguably the best commentary I have ever read on any book of the bible, especially the Gospel of John. Carson is consistently evangelistic, committed defending the Gospel and answering the best critics such as Rudolf Bultmann and C.H. Dodd, as well as redeeming the valuable material that the critics have produced. Carson also quotes the best arguments from other excellent commentaries such as The Gospel of John by F.F. Bruce. Indeed everything is in this one book, and this is demonstrated by 300 books listed in its bibliography.
One of Carson's best qualities, is that he will provide each argument, and then state which argument is the best, unlike other authors who are unwilling to risk being wrong. If you questions on anything in John from Philo's Logos to the Essenes to Passion Week timings to the pericopes to the John 21 appendage, Carson will have your answers. Go get it today! (Read online preview here).
Related: C.H. Dodd, Commentary, d.a. carson, F.F. Bruce, Rudolf Bultmann, The Gospel According To John