I have recently finished reading through John Ashton's second edition of his work Understanding the Fourth Gospel (OUP, 2007), and it is not merely the Technicolor version of the original publication (1991), although it may look that way. His introduction has had a significant overhaul in the second edition that streamlines the discussion, but the first edition's introduction may offer further background for readers on the state of play prior to Ashton, especially regarding Bultmann's contribution. The second edition has some rearrangement of chapters and four new excursuses.
John Ashton's overall study remains the same: he argues for the importance of the theme of revelation in John's Gospel and disagrees with Bultmann's conclusion that all Jesus reveals is that he is the Revealer. Ashton concludes that the mode of the revelation, the gospel, has a part to play in the revelation. For the Fourth Gospel, revelation is not just about Jesus' words or the telling of heavenly revelation. The revelation is acted out in the life of Jesus, in the logos ensarkos (the Word enfleshed). Jesus acts and speaks what he has seen and heard from the Father. Because of the importance of action as well as word, the Evangelist has used the gospel form to proclaim this revelation. In this way, as Ashton states: 'the medium is the message' or the mode of the revelation is the revelation.
Two other points of interest that run throughout the book are Ashton's emphasis on the importance of diachronic study of the Gospel and what he sees as the two-level nature of the Gospel (á la Louis Martyn). These two points have obvious relationship with each other. Ashton contends strongly for the importance of the diachronic study of John along with synchronic study. He finds narrative approaches that only address the text of the Gospel (synchronic) to be unhelpful. For him, proper study of the Gospel of John means making judgments about the development of the text and of the author(s) or community that were involved in its development. Ashton makes this same argument in 'Second Thoughts on the Fourth Gospel', in Tom Thatcher (ed), What We Have Heard From the Beginning: The Past, Present, and Future of Johannine Studies (Baylor, 2007). The first 140 pages of Understanding are his argument for this approach, his explanation of this community, their struggles with 'the Jews', and their connection to the Gospel. He then uses this background throughout the rest of the book to interpret the Gospel and explore the theme of revelation within it. Ashton has shown some of the pitfalls of narrative approaches in that they are often unconnected from history, but if his description of the situation and reason for authorship of the Gospel are incorrect, this negatively influences the interpretation of the Gospel. A faulty lens can lead to misunderstandings of the text. Narrative approaches or world within the text approaches sometimes purposely avoid the historical questions either because what Ashton has done in Understanding takes too much effort or because the difficulty of coming to an accurate conclusion is recognized as the problematic exercise that it is. Ashton makes a important call not to forget the development or at least the situation of writing in our exegetical endeavors, but I think we must likewise be careful in the application of any historical models.
[Comments on John Ashton's The Gospel of John and Christian Origins (Fortress, 2014) may be found here.]