Authenticity of the Holy Bible

This is a question addressed to more mature believers/ministers. I am in the nascent stages of understanding the call of God upon my life, and so I apologize if this is somewhat elementary to some readers. As well, may I just state that I am a firm believer in the Word of God (the Bible), the finished works of Christ, and the activity of the Holy Spirit on the Earth today; I am in no way a skeptic, or someone here just looking for attention: If it is historically proven (and I believe it is) that there were many more historical accounts written about and around the time of Jesus, how is it that only a select few (the complete Bible as we know it, which comprises 66 books) made it through the "... given by inspiration of God ..." filter, as expressly stated in 2 Timothy 3:16. What disqualified other anecdotes and writings? Who made this determination? I ask this bearing in mind that the Catholic Church was the most influential Christian leadership available in those periods before the Reformation. I believe the Bible to be the unadulterated Word of God; I just want to be certain as to why I do. Any helpful comments on this matter, especially by mature ministers would be appreciated. Thank you