When you approach the New Testament – and the Bible as a whole – as though it were a single text, implicit to that approach is a belief in an ahistorical unity of composition, as though the individual books were written with the intention of becoming a single volume. But this was not the case, and as the individual books of the New Testament were being written, there is absolutely no evidence that there was any thought given to compiling them into a single volume. That single volume was assembled by others, centuries later, and in response to very specific and particular historical conditions – to say nothing of the fact that the texts were then edited to agree with one another doctrinally. One glaring example of this comes from the very opening lines of the Gospel of Mark, which in later versions of the text have the words υἱοῦ θεοῦ (“son of God”) added. These are notably missing from our earliest extant copy of Mark, the Codex Sinaiticus, which anyone can verify online.
So for example, when you point to the fact that the Gospel of Mark never disputes the claim that Jesus is God, you claim that this is evidence of support for Jesus’ divinity. But of course the author of Mark never disputes Jesus’ divinity: it is never explicitly stated anywhere in Mark that Jesus is God. If the author of Mark went around saying, “And Peter was not God, and Mary was not God, and Joseph was not God, and Simon was not God, and Thomas was not God,” then I would say, Sure, because Mark said everyone else is not God and never said that Jesus was not God, then that makes me think that he is hinting at the idea that Jesus is God. But the author of Mark does not do that. And just because the author of Mark does not explicitly refute that Jesus is God does not mean that he proclaims that Jesus is God. This is not a reflection of my personal belief, either; this is an exercise in logic: Just because one thing is not true does not mean that the other thing must be true. Likewise, what relevance does what is written in the Gospel of John hold to what is written in the Gospel of Mark? John and Mark were (1) not written at the same time; (2) not written by the same author; (3) possibly not even written in the same geographic area; (4) written with different emphases; (5) written with different audience in mind; (6) reflect differences and, in the case of John, developments in theological thinking not present any of the other canonical gospels; and (7) separated in time by a half century or more.
Scientifically speaking, you cannot simply decide to read one text in the context of another because you believe that they match. Church Fathers did that later, yes, but historically speaking, the authors of the gospels were not cooperating with one another, nor were they operating under the assumption that their texts would be read together at the same time, in the same place, by the same audience, etc. Adding that particular layer of interpretation – reading one text in the context of another – does not preserve the integrity of what is written, but implicitly changes emphasis through the new context and can, in the worst cases, force what is written to say what the interpreter chooses.
The fact that something is written in John, Matthew, or Luke does not mean it has any bearing on what the author of Mark wrote, particularly since Mark appears to have come first and influenced the others – and yet even then we find problems, for it it even seems that what is in Mark did not influence what was subsequently written in John since much of what is included in Mark remains absent from John. For that matter, the Gospel of John is an incredibly problematic historical document, not simply because of the aforementioned theological developments not present in any of the three other canonical gospels, but because its status as an outlier makes it clear to historians that it must be considered on its own individual basis – more than even Mark, Matthew, and Luke.
The evidence from one book (John) cannot support your interpretation of what is written in another (Mark). This is fundamentally ahistorical and not a logical or scientific approach to the understanding of these earliest Christians. It would be the same thing as stating that a book written by a Republican politician in 1963 on the subject of slavery has any bearing on what another Republican politician, Abraham Lincoln, wrote on slavery in 1863 – they have nothing to do with one other but for both being on the subject of slavery and both being written by Republican politicians. Now imagine that you are standing in the year 2225. Now 1863 and 1963 suddenly seem a lot closer together in time, and the trend is, historically speaking, for people to conflate the thinking between any given moments in time the further they are removed from the events in question. Now what are clearly isolated examples of American opinions on slavery can be transformed into a spectrum of political policy that spanning the course of 100 years. That is again an obviously ahistorical approach to the subject since -for no other reason – that a great deal transpired between the years 1863 and 1963, to say nothing of the drastically changed historical contexts between the two moments of writing. More immediate to the present, imagine for a moment what was written about international terrorism in 1970 when compared with what will be written in 2020; the events of September 11, 2001, alone demonstrate how much one event can change the world, to say nothing of American thinking in the mere span of half a century.
Put more simply, these are a priori conditions under which you are operating in so far as you have already established the conclusions which you are seeking and therefore read the evidence that you find as fitting with that conclusion. When you consider the texts in a historical fashion, however, you must consider them on an individual basis – one can not simply create a “gospel-of-the-mind” from an assemblage of the four selected gospels selected to be a part of the canon of the Roman Catholic and Protestant New Testaments. Persisting in reading the text as though it were hand-delivered from heaven as a single text, in that the individual authors were not acting on their own individual agenda, and in not seeing past the accumulated accretions of history (e.g. developments of doctrine, changes in interpretation, changes in emphasis of belief) create conditions which do not allow one to truly understand the original intentions or beliefs of those earliest followers of Jesus.
