St. Paul does not add to that "and nothing else."
***Paul’s defense is to say that HE believes what is written in the only scripture he had, the books of the old testament, the law and the prophets.
St. Paul does not add to that “and nothing else.”***
St. Paul also has no clue that some of his letters and other attributed to him will wind up as Scripture as a decision by the Church 250 years later.