wrong, wrong, wrong. the Septuigant was the OT of the early Church and it contained more than your 39 books. there was no “common use” of the NT, many books claimed to be Scripture and certain books like Revelation were not accepted by everyone. The Church settled the question in the 4th century, and did not come up with 66 books.
please provide me the name of any group before the 16th century that used a 66 book Bible, i have never heard of any. The One, Holy, Catholic and Apostolic Church has never used a 66 book Bible. 1,500 years is a long time to have the wrong Scriptures, don’t you agree?
btw - When the Church set the canon in the 4th century, it was not in reaction to any “Protestants”. it would be another 12 centuries before they came on the scene.
You obviously didn’t read the article at the link.
Cyril of Jerusalem on the Canon - From his Catechetical Lectures, iv. 33-37, about A.D. 350.
33. Now these the divinely-inspired Scriptures of both the Old and the New Testament teach us. For the God of the two Testaments is One, Who in the Old Testament foretold the Christ Who appeared in the New; Who by the Law and the Prophets led us to Christ's school. For before faith came, we were kept in ward under the law, and, the law hath been our tutor to bring us unto Christ. 1 And if ever thou hear any of the heretics speaking evil of the Law or the Prophets, answer in the sound of the Saviour's voice, saying, Jesus came not to destroy the Law, but to fulfil it. 2 Learn also diligently, and from the Church, what are the books of the Old Testament, and what those of the New. And, pray, read none of the apocryphal writings: 3 for why dost thou, who knowest not those which are acknowledged among all, trouble thyself in vain about those which are disputed? Read the Divine Scriptures, the twenty-two books of the Old Testament, these that have been translated by the Seventy-two Interpreters. 4
Council of Laodicea (about A.D. 363).
It is proper to recognize as many books as these: of the Old Testament, 1. the Genesis of the world; 2. the Exodus from Egypt; 3. Leviticus; 4. Numbers; 5. Deuteronomy; 6. Joshua the son of Nun; 7. Judges and Ruth; 8. Esther; 9. First and Second Kings [i.e. First and Second Samuel]; 10. Third and Fourth Kings [i.e. First and Second Kings]; 11. First and Second Chronicles; 12. First and Second Ezra [i.e. Ezra and Nehemiah]; 13. the book of one hundred and fifty Psalms; 14. the Proverbs of Solomon; 15. Ecclesiastes; 16. Song of Songs; 17. Job; 18. the Twelve [minor] Prophets; 19. Isaiah; 20. Jeremiah and Baruch, Lamentations and the Epistle [of Jeremiah]; 21. Ezekiel; 22. Daniel.
AD 400 - Jerome translates the Bible from Hebrew and Greek into Latin (called the "Vulgate"). He knows that the Jews have only 39 books, and he wants to limit the OT to these; the 7 he would leave out (Tobit, Judith, 1 Maccabees, 2 Maccabees, Wisdom of Solomon, Sirach [or "Ecclesiasticus"], and Baruch--he calls "apocrypha," that is, "hidden books." But Pope Damasus wants all 46 traditionally-used books included in the OT, so the Vulgate has 46.
So your hard facts fall short, here is evidence in two places of the use of a smaller bible - based upon the Jewish canon from Jamiah in the 1st/early 2d century.