That’s a deduction and inference but it isn’t clear Peter considered Paul’s writing the same kind of holy writ as they did the Law and the Prophets. I mean it doesn’t just say “Paul’s writings are scripture.” So I’m lead to believe they weren’t considered holy writ at the time they were written.
The Colossians 4 passage, from my perspective, doesn’t really say the epistles were widespread. We at least know the Colossians epistle was in Laodicea, but that’s all. Actually, it seems to say we’re missing an epistle called Laodiceans from the canonized Bible.
As far as the Bereans go, they were certainly looking to the Old Testament books as their scripture considering they were Jewish.
Acts 17:10,11
10And the brethren immediately sent away Paul and Silas by night unto Berea: who coming thither went into the synagogue of the Jews. 11These were more noble than those in Thessalonica, in that they received the word with all readiness of mind, and searched the scriptures daily, whether those things were so.
Acts 17:10,11
10And the brethren immediately sent away Paul and Silas by night unto Berea: who coming thither went into the synagogue of the Jews. 11These were more noble than those in Thessalonica, in that they received the word with all readiness of mind, and searched the scriptures daily, whether those things were so.
I Timothy chapter 5
[17] Let the elders that rule well be counted worthy of double honour, especially they who labour in the word and doctrine.
[18] For the scripture saith, Thou shalt not muzzle the ox that treadeth out the corn. And, The labourer is worthy of his reward.
Here, Paul quoted two scriptures...one from Deuteronomy, and one from Luke 10:7.
In fact, Paul's quote is an exact match of part of Luke 10:7 in the underlying Greek.