The question is not what you confine "truth" to, the question is what Paul meant by truth.
No . . . that's
your question. Since when do your questions take precedence? However, I will address this question, with hopes that perhaps you will be gracious enough to address a few of mine.
What did Paul mean by Truth? He was referring to the Gospel, the Gospel which was bestowed upon Him by direct revelation of the Holy Spirit. I'm pretty sure I said that once already?

Today, 2000 years later, the only way "I" know what Paul believed and taught is by reading my Bible.
What do you assert that Paul meant by "truth?" And to what do you owe your enlightenment to this fact? IOWs, how do
you know what Paul meant by "truth?" In fact, how do you know what Paul meant about anything?
I know what he believed and taught because of the numerous letters/epistles he wrote to other churches instructing them. How do I know what his letters said? Because I have a Bible which contains those letters.
Now, another question for you. How
does this relate to the question "what is the pillar and foundation of truth?" I mean, even if you and I do not understand the truth to be the same thing, does that change the identity of the Pillar and Foundation of the truth of which Paul spoke? I mean, it doesn't matter if you and I have different understandings. The OP speaks of the "pillar and foundation" of the Truth which Paul spoke. It does not question the truth as you or I may perceive it. So, in regards to the OP, your question regarding the identity of truth is moot.
However, if it is your wish to establish that I am ignorant regarding the identity of the "truth," you must first establish an authority to do so. You would begin by establishing the exact "scope and authority" that accompanies the privilege of being "the Pillar and Foundation of Truth." If you can claim that authority for your faith, if you can substantiate this assertion, then you may
tell us what "Truth" is.
Anyhow, back to Paul, did he restrict that truth to the Bible? I'm sure that since the Bible was yet to be compiled he did not, but it was
Scriptural. We know this from what Peter taught.
2Pe 3:16 As also in all [his] epistles, speaking in them of these things; in which are some things hard to be understood, which they that are unlearned and unstable wrest, as [they do] also the other scriptures, unto their own destruction.
So, Paul may or may not have been aware that his teachings were to be considered
Scripture, Peter did, which makes it nearly impossible to presume that Paul did not.
You and Iknow that the truth is contained in the Bible, because we have our bibles.
That is why I said, the truth given to US in the Bible. "Us" includes you, me, Ricky, Lucy, Fred, Ethel, Ed, Trixie, Ralph and Alice. Not Paul--the Apostle.
Once again, I didn't state that I mean a building to be the pillar and foundation of truth. That would be illogical, wouldn't it?
Okay, my terminology is a bit off in this statement. So, do you or do you not argue that the "Church" (as you define it) is a visible/tangible entity as do RCs and EOy? I've explained once that I'm approaching this based upon the arguments between those two faiths and the Protestant faiths, visible/tangible vs. Spiritual body.
You implied that to believe the (c)hurch to be a "spiritual body of believers," implies that we believe the (c)hurch to be a "worldwide amorphous group of Christians." BTW, you never answered my question as to whether or not you believe that Christianity is a worldwide faith. Do you?
It proves no such thing. Nothing in the letter says that. All we know is that there is a letter and what is contained therein. Whatever your personal feelings about what "Paul felt", they have no bearing on the identity of "truth" as only scripture.
I did not say that the letter
said that. The letter does not have to say that in order for us to come to this logical conclusion.
1Ti 3:14 These things write I unto thee, hoping to come unto thee shortly:
So, why if we are to believe that the Apostles entrusted any teaching necessary regarding salvation to be passed on for centuries in oral form only, why didn't Paul just tell the messanger something like, "Hey, I'm running behind. I want to go ______, but I don't know when I'll get to. But, they need to know a couple of things. So, I want you to go on ahead and
tell them I said . . . . ?"
We don't know how many messengers he may have sent.
Well, we know he wrote more than one letter, because of the Bible. No, we don't know how many messengers he sent, but that's no reason to assume that he sent any with verbal instruction. Lack of proof that the did not send more is not evidence that he did send more.
Your personal feelings have no bearing on what Paul wrote.
Um . . . the OP asked for comments. Am I to be strung up for accomodating him?
The question at hand is---- What did Paul mean by truth?
Whose question? Nobody's but yours. That is not what the OP asked. He asked what the "Pillar and foundation" of truth is. What I believe Paul to be speaking about or what you believe him to be speaking about doesn't matter. The OP refer's to Pauls truth. When I said, ". . . truth given to you and me in the Bible," I was not implying or claiming a to possess a different Truth than Paul's. I only know Paul's truth from what I read in Scripture. If you have another source quoting Paul teaching something extrabiblical, I'm all eyes. Refer me to it.
In fact, the OP didn't even ask what
Paul considered to be the "pillar and foundation of truth." He asked us what we believed it to be. So how do you justify jumping in here and reidentifying the topic/question?
If you assert that he meant "scripture only", it's encumbent upon you to prove that from Paul's writing.
No, it's not. First of all, I never implied that Paul meant Scripture only. You've read far to much into my statement. This circular discussion is ludicrous. You're not addressing the OP or my comments.
If you wish to assert that there is a different truth or more truth than what is in our Bibles, it is encumbent on you to prove that and substantiate your arguments with a identifiable/documentable source. Also, it is encumbent upon you to prove that there is more to the Truth than what Paul referred to in Scripture.
Are you trying to say that all teaching in church took place only by letters or when one of the apostles happened to be around that year?
Well, what do you suggest? How else were the teachings passed on? How would you prove this? How did we come to have a Bible if written epistles and teachings weren't necessary? Why did they write anything down?
Quite an improbable and illogical premise if you ask me and one completely unsupported by scripture and history.
Really? I think I've already given you evidence from Scripture. I'm curious, how do you propose to prove from History that teachings were passed on in oral form only? Anything you find in history is found by reading it, which is a pretty sure bet that it's written down
somewhere.
2 Thes 2:15 So then, brothers, stand firm and hold to the teachings we have passed on to you, whether by word of mouth or by letter
This says what to you? To me it instructs us to adhere to the Gospel/Truth, that we are bound by it whether we
read it or
hear it preached. He is differentiating between modes of delivery/receiving, not separate sources of information.
We know that Paul is not confining "truth" to scripture of the jews,
Never implied that he did.
and there is simply no scriptural proof that Paul is confining "truth" to future scripture.
You amaze me. Did I ever say that Paul confined the Truth to any place or ideology? No, I did not. My assertion is the only way I know what Paul taught or believed is by reading what is in my Bible.
However, I've already shown where Peter identified Paul's teachings as Scripture.
Therefore, he must be speaking of "truth" in a way that is not confined to scripture.
Again, I never implied that Paul confined truth to anything. Maybe confined is the wrong word. It should be stated that Scripture is comprised of the Gospel/Truth.