The Old Testament Scriptures most certainly were used extensively by the first Christians and Jesus referred to them numerous times to show that Moses and the Prophets spoke of Him. The early believers also had the benefit of being in the presence of Jesus, himself, and his personal teachings or with the Apostles or their direct disciples who continued teaching the same truths. The early churches had leaders installed by the Apostles who had been vetted to ensure what they knew and taught was the same and, afterward, they received the letters written by Paul, Peter, John, etc. as they were written and copied and dispersed throughout the regions. This is why there are literally thousands of extant copies of the ancient documents still around and held in collections and museums.
Lastly, I take issue with your MIS-interpretation of I Timothy 3:15. The Church is NOT the "basis and pillar of the truth" but "a pillar and buttress of the truth". In other words, it is supposed to uphold and be the foundation of the truth not be the "basis" of it. That's why God gave us Holy Scripture. Any church which fails to do that is a false one. If anyone preaches a gospel other than the one we have in Scripture, they are preaching an accursed gospel.
This is an important statement. Our King walked and spoke with so many...imagine.... they were speaking with Lord face to face!
I think we forget that Jesus wasn't always teaching....He was enjoying the company HE kept and they Him....just as we do now.
Though i have not seen this verse infallibly defined, RCAs lay much weight upon this verse in contending this refers to Rome being the assuredly infallible instrumental source of and authority on truth, even though (or because) the text only says "church of the living God, the pillar and ground of the truth," in which the words rendered "pillar and ground" (DRB) or "pillar and foundation" (NAB) - "stulos" and "hedraiōma" - both denote support(ing). The former is used as "pillar" elsewhere while latter only occurs here in Scripture, and while it comes from a word which can mean support in the sense of ground, is not one of the words used for foundation, (katabolē, themelios) collectively 22 times, and which Christ is said to be. (Some believe the pillar and ground in this verse refer to the living God.) The word of "of the" (truth) is only one word, and can be rendered "to the" (Mt. 5:25) but here "of the" would seem to be required.
Vines states "Στύλος pillar, in Paul only Gal_2:9. In Rev_3:12; Rev_10:1. Ἑδραίωμα stay, prop, better than ground. N.T.o. olxx, oClass. The kindred adjective ἑδαῖος firm, stable, 1Co_7:37; 1Co_15:58; Col_1:23. These words are in apposition with church.
The idea is that the church is the pillar, and, as such, the prop or support of the truth. It is quite beside the mark to press the architectural metaphor into detail. By giving to ἑδραίωμα the sense of stay or prop, the use of the two words for the same general idea is readily explained. The church is the pillar of the truth, and the function of the pillar is to support."
And again, that "the church of the living God, the pillar and ground of the truth," refers to the church being just that finds no objection with us under SS, for the church upholds the truth, the Scriptures being the assured word of truth, while the church is also "of the truth" in being built upon truth, principally the truth of Peter's Scriptural confession, and thus Christ Himself, "On the rock of this faith confessed by St Peter, Christ build his Church,” (CCC, pt. 1, sec. 2, cp. 2, para. 424).
The upholds this truth most primarily by preaching "the word of the truth of the gospel," (Col. 1:5) which "now is made manifest, and by the scriptures of the prophets, according to the commandment of the everlasting God, made known to all nations for the obedience of faith: " (Romans 16:26)
But using this verse to uniquely refer to the Roman Catholic Church and its assuredly infallible magisterium (AIM) under its petrine papacy, perpetuated thru apostolic succession - all of which it must according to their private interpretation of it - requires
a level of extrapolation which relates to and is akin to the attempts to force Mt. 16:18 and other texts to refer to the same, which they will not do individually or collectively, nor is premise that a perpetual AIM is necessary to preserve Truth Scriptural.
As said, unto the Israelites "were committed the oracles of God" (Rm. 3:2) and "to whom pertaineth the adoption, and the glory, and the covenants, and the giving of the law, and the service of God, and the promises; Whose are the fathers, and of whom as concerning the flesh Christ came, who is over all, God blessed for ever. Amen. " (Romans 9:4-5)
Yet Scripture was given and established, and truth was preserved without an assuredly infallible perpetual magisterium of men, but the Scriptures were established as the perpetual assured word of God, and standard for obedience and testing truth claims, and so it is today.
The Old Testament Scriptures most certainly were used extensively by the first Christians and Jesus referred to them numerous times to show that Moses and the Prophets spoke of Him.
In the smaller towns and villages, there was often only the rabbi who could read. Early Christians did not use the OT much - read Paul and realize that the OT meant nothing to the Greeks. Jesus and the Apostles used the OT on Jews, not Gentiles. The pagans did not care about the OT much, and by the time of the Nicene Council, they were not read at all. It took decreeds by Popes and bishops to get them included again.
The early churches had leaders installed by the Apostles who had been vetted to ensure what they knew and taught was the same and, afterward, they received the letters written by Paul, Peter, John, etc. as they were written and copied and dispersed throughout the regions. This is why there are literally thousands of extant copies of the ancient documents still around and held in collections and museums.
And many of the 'letters' were written by unknown people well after their deaths. Or we simply don't know anything about them. Who was 'Jude'? When were 1 Peter and 2 Peter written and who by? Who wrote Hebrews? Not that it matters overly much; the Church has decreed that they are Scripture and Scripture they are.
Lastly, I take issue with your MIS-interpretation of I Timothy 3:15. The Church is NOT the "basis and pillar of the truth" but "a pillar and buttress of the truth".
Find me a translation or a Greek version which says that. I'll bet you can't.
That's why God gave us Holy Scripture. Any church which fails to do that is a false one. If anyone preaches a gospel other than the one we have in Scripture, they are preaching an accursed gospel.
Jesus gave us the Church which He taught for three years. NT Scripture is a gift from the Church, aided by the Holy Spirit. You're welcome.