A commenter in another thread has cited Ben Witherington’s theory that the fourth gospel was authored by Lazarus. Much of what I said in my review of Richard Bauckham’s book is applicable to Witherington’s theory. Also, see the comments about authorship by Lazarus in Bauckham’s book, in Craig Keener’s commentary on John, and in D.A. Carson and Douglas Moo’s New Testament introduction.
A lot could be said, but I’ll just add a few comments to what I’ve said before and what’s contained in the sources mentioned above. The extant early sources we have convey a lot of information about a prominent church leader named John (his old age, the time of his death, where he resided late in life, some of the events he was involved in late in life, etc.). They attribute five documents to a prominent John, and none of the earliest sources distinguish between multiple Johns. If Ben Witherington is correct, then there was universal error among the extant sources not only on the authorship of the fourth gospel, but also on the authorship of three other documents, the Johannine epistles. And multiple sources report that disciples of a prominent church leader named John lived well into the second century. Polycarp didn’t die until the second half of the second century. Under such circumstances, with Johannine disciples around and prominent for so long, it’s unlikely that four documents would be so widely accepted as written by such a prominent John if they were all instead written by Lazarus.
Bauckham’s theory at least has the advantage of giving far more of an explanation of the external evidence than Witherington’s theory does. The ease with which Witherington dismisses the external evidence is reminiscent of the faulty reasoning of the sort of liberal scholarship that Bauckham’s book refutes. And it can’t be argued that the external attestation to somebody named John doesn’t begin until late in the second century. Sources like Justin Martyr, Irenaeus, and Origen suggest that attributions to John were occurring well before the late second century, both among heretics and among the orthodox.
Regarding internal evidence, I would recommend that people look up the passages Ben Witherington cites and read the surrounding context and the relevant Synoptic passages. I think that Witherington sometimes leaves out details that weaken his argument. Everything he mentions is non-explicit and can plausibly be read in a manner consistent with authorship by the son of Zebedee. (See, for example, Craig Keener’s comments, in his commentary on John, regarding many of the issues Witherington raises.) John 11, in addition to referring to how Jesus loved Lazarus, refers to how Jesus loved Mary and Martha (verse 5), and the passage goes on to distinguish between the “friend” Lazarus and the “disciples” (verses 11-12). When later chapters refer to a disciple Jesus loved, it could be that the initial readers of the gospel were expected to usually associate “disciples” with Jesus’ closest followers, particularly the Twelve in a context like John 13. In other words, the term “disciple” may have been most naturally interpreted by the initial audience in a manner that would exclude somebody like Lazarus, much as John 11:11-12 distinguishes between Lazarus and the disciples. The fact that both Lazarus and the beloved disciple are said to be loved by Jesus doesn’t change the fact that the use of the term “disciple” and the context of passages like John 13 may have been sufficient for the earliest readers to distinguish between the two. The emphasis on Jesus’ love for Lazarus in John 11 does add some weight to Witherington’s theory, but not as much weight as he suggests and not nearly enough to counter the large weight in favor of the son of Zebedee both internally and externally.
I think that Witherington also is wrong in his reading of some of the other internal evidence, such as the closing of the gospel. John 21:23 tells us that Jesus’ comment in John 21:22 is the reason why a belief arose about how long the beloved disciple would live. Since verse 23 sufficiently explains why the belief arose, there’s no need to speculate that the belief may have risen or spread because the beloved disciple had been resurrected.
Again, a lot more could be said, and I recommend reading my review of Bauckham’s book and the other resources mentioned above for more on this subject. I’ve said that I consider Bauckham’s theory the second best explanation of the evidence. I don’t know how high I’d rank Witherington’s theory, but even if it were the third best, I’d rank it as a distant third.