Some may argue that there was a gradual evolving of thought concerning the NT and only after a long period did these writings come to be regarded as an authoritative source of scripture to the Christian Church, but that does not seem to line up with correct historical reality...
Yes, in fact, it does line up quite accurately.
When those who were called and inspired by God in the first century wrote, their letters were immediately acknowledged and accepted by throughout the church. They "continued steadfastly in the apostles' doctrine" (Acts 2:42) and they received those teachings "not as the word of men, but as it is in truth, the word of God" (1 Thessalonians 2:13).
Who said they were "writings"? They were "teachings" that they received, not "scriptures" If you use these two verses to support they had the NT, bear in mind the only writings they could possibly include would be Matthew, Mark, and a number of Paul's letters. That's it. That would have excluded Luke/Acts, John, Revelation, and so forth. No, these verses do not support that they had a NT they were using.
BTW, there were a lot of others texts that were immediately acknowledged and used in the church too, that hit the editors floor in the 3rd Century. So the fact it was used was not a criteria for inclusion. Fact.
These writings were received as "Scripture".
Will you support this with a source of authority? Did Paul ever say, "I am writing scripture?" Did he ever say, "You have the scriptures I wrote for you", to any of the churches? No?
The word "Scripture" is used about 50 times in the New Testament and always refers to the written record of the will of God.
It refers to the OT books, when not later 2nd century pseudepigraphal texts that got added into the Bible as "scripture".
Thus, the word "Scripture" can accurately be applied to the things found in both the Old and New Testaments.
You can include my writings too as scripture then when I speak of my experience of God and understanding what His will is, if the criteria for scripture is talking about the will of God.
It is simply not true that these writings only came to be accepted as scripture along with the OT at a later date because we know that these inspired writings of the first century were circulated among Christians and regarded as scripture and authority for the churches (Col. 4:16 and 1 Thess. 5:27). Paul (writing in about 65 A.D.) quotes Luke's gospel and refers to it as Scripture (see 1 Timothy 5:18 and Luke 10:7). Peter (in 66 A.D.) mentions Paul's writings and calls them Scripture (2 Peter 3:16).
The Apostle Peter wrote neither of the epistles in his name, especially 2 Peter. Critical scholars, using modern methods of analysis, date that epistle somewhere between 100-160 AD. So yes, a pseudepigraphal work of the 2nd century, would speak of Paul's writings as authoritative, since 2 Pe. is written in the Pauline succession. And if Paul considered his teachings as "authoritative", that does not mean he viewed his letters as "scripture", comparable to the Torah. He was a church-establisher, and his authority as a leader was what he was arguing for. As far as 1 Timothy, again, pseudepigraphal, not written by Paul, but someone of the 2nd century. So anything they say about "scripture" has to be taken with a view from a later period looking back on early Christian formation, as competing against other early Christianities with their particular views which differed from the other schools of thought. As far as Luke's gospel reference, it's quoting Deuteronomy 25:4, which last I checked is considered a book in the OT, unless someone moved it to the NT.
But here's another point. They also considered other writings which got tossed onto the editors floor in the 3rd century, to be useful in services and considered integral to Christian practice in early church. So much for "preserving the word". Someone much later decided via committee and politics, what they felt should and shouldn't be included, excluded the actual use of actual Christian churches who viewed those texts as inspired too! These men decided if it fit their idea of Christianity or not. That has NOTHING to do with divine inspiration, but politics and administration. No, it's not this wonderful rosey mythology you have imagined was involved in "preserving the word". That's a myth.
Now, of course you can choose to ignore modern scholarship in favor of your beliefs, but that's nothing that will convince others who accept modern scholarship. It's like denying evolution or the age of the earth to rational modern man, or that the earth is a flat disk with ice walls to keep us from falling off. But at the least you can see we in fact have an actual basis for our points of view, and how they inform our faith, right? That we think of it in different terms, that include modern rational and empirical points of view and we integrate faith with it, does not give you license to witch-hunt others over things outside your wheelhouse. It only makes you look bad, and says nothing favorable about how you see others with different points of view, as a Christian.
There were several writers who made frequent appeal to the authority of what we now know as the New Testament books within the first 50 years after the apostles. Clement of Rome, in his Epistles to the Corinthians (A.D. 95) makes reference to Matthew, Mark, Hebrews, Romans, 1 Timothy, Titus, 1 Peter and Ephesians. The epistles of Ignatius (A.D. 115) and Polycarp (A.D. 130) refer to various New Testament books. Justin Martyr (A.D.100-165) made extensive appeal to the four Gospels and mentions Acts and Revelation.
Revelation barely made it in the choices of what to keep, and was actively opposed by many prominent religious leaders of the time. A real pity that one didn't hit the dustbin, consider how it's created the sorts of "make it say anything you want against any opponent you have" book throughout the ages. It's a really magnet for the conspiracy theory types too, I'll add.
The title "New Testament" may not have been used until near the end of the second century. But, the inspired writings that make up the New Testament were well known, widely circulated, and regarded as Scripture among Christians of that era.
As were many other book widely circulated and used and considered scripture too. Where are they? Oh, that's right, they were ordered burned! But thankfully many were preserved and rediscovered in the last century, giving the world a look at the real world of early Christianities, the real world behind the layers of later myth superimposed upon it.
Again, these are things you learn when you expose yourself to modern scholarship - with an open mind, as opposed to simply trying to fault-find, like this whole irrational BS about meditation opening to you Satan.