The Book of Revelation was just finished in 96 AD by Apostle John, now how can the apostles have a complete set of 73 Books compiled in one book ? Again, never did the apostles stated that the authority is the bible, if they believed in the heretical and unbiblical sola scriptura, then the Council of Jerusalem should have never been convened to begin with, but of course it did not. In ACTS 15, the Council of Jerusalem, all the apostles listened and agreed to the dogmatic truth that Peter declared that circumcision is non binding in the new covenant, an issue Paul and Barnabas could not settle by their own personal interpretation, now if sola scriptura and protestantism is true, then why did all the apostles were present during this important first council of the church ? If sola scriptura is true then the apostles should have started their own cult or sect.
2ND, who said that the Holy Bible or Canon of Scriptures did not come from the Lord ? The church infallibly declared it to dispel false gnostic gospels circulating in the 4th century. The church exercised its authority to declare the universal truth to the whole church the divinely inspired books inspired by the Holy Spirit, just like when the church declared the Dogma of the Trinity in the 3rd century to counter the Arian heresy. The Holy Bible itself is a declared (canon) doctrine of the church, nowhere in scripture states that the church would define, codify and canonize the Divinely inspired books compile in one book.
3RD, the Greek Canon (Septuagint LXX) was the standard canon of the ancient jews and the apostles. The Greek Canon was crucial in writing the New Testament Canon, there are 300 quotes from the Greek Canon that was used by the inspired writers of the new testament, to reject the Septuagint LXX (Greek Canon), is rejecting the New Testament Canon. Now where did Luther and all protestants got the authority to remove, manipulate and tamper books in the bible ? Protestantism rejects the New Testament Canon itself, just like rejecting the Sacraments established by Jesus.
4TH, Yes, you said it, 2 Peter 1:20-21 states that scripture is not subject to someone's own personal interpretation which destroys sola scriptura and protestantism. Protestantism has a 500 year history of false end time prophesies to promote the false apostate jewish created dispensationalist heresy.
5TH, 2 TIM 3:16 just states that ALL Scripture is useful, it does not say that ONLY Scripture is useful. Paul never said scripture is the only thing needed for a Christian's approval and doctrine. That is erroneous, because if that is the case, then he (Paul) would not have participated in the Council of Jerusalem and the decisions of the church to replace Judas and the dogmatic truths declared by Peter in the council. The operative word is "ONLY" and nowhere in that verses says the word "ONLY". If Paul did say that, then that would be a contradiction of his very own words in 2 THESSALONIANS 2:15 that says that it is through Sacred Tradition that we learn our beliefs.
2 THESSALONIANS 2:15 -Therefore, brethren, stand fast; and hold the traditions which you have learned, whether by word, or by our epistle.
Paul only states that scriptures are good for instruction and teaching (teaching tool). Paul's letter (epistle) to Timothy was not Scripture when he wrote it, so Paul was referring to the Greek OT (Septuagint, again books that protestant rejected and refuse to call Scripture), so they are not obeying Paul), since Timothy did not read Hebrew. So Paul was saying, "All the Septuagint is inspired by God and profitable for ... "
But the next, even bigger, point is that Paul was acting out Tradition when he wrote this to Timothy - he was not an original Apostle but was added to the Church (baptized) by Ananias of Damascus, and finally confirmed by the Apostles in Jerusalem, granting him authority and apostleship. And Paul, using his apostolic authority made Timothy a bishop also. If Paul's writing carries any weight or validity, it is because he is the Authority of Tradition in Action and in Person. This makes Paul's statement to Timothy really say this: "Timothy, I, Paul, by my Authority to define what teaching you follow say to you that you must also give authority over yourself to all the Septuagint like you have me as an authority over you in Christ, since it is profitable for ..."
Every bishop, that acts in accord with this Tradition carries the same authority today as Paul did. We trust the Bible BECAUSE WE ARE OBEDIENT TO OUR BISHOPS, OBEDIENT TO THE MAGISTERIUM, OBEDIENT TO OUR HOLY FATHER, AND THESE LIVING PEOPLE TELL US WHAT SCRIPTURE WE CAN TEACH FROM, CORRECT WITH, AND TRAIN IN RIGHTEOUSNESS WITH. We trust the Bible because the leadership we trust gives it to us, not because of some stand-alone idea about a book that came from the sky.
Again, Jesus established a church, stop bowing down to your own personal interpretation.