One of the things scholars don't know and which is one of the unheard truths of the Bible. Maybe this is the first time you are going to hear this; all the apostles and all the elders of the church wrote a particular book in the first century, all of them co-operating with one another and the active members of the church. In Acts 15:19-20;
19 "Wherefore my sentence is, that we trouble not them, which from among the Gentiles are turned to God.
20 "But that we write unto them, that they abstain from pollutions of idols, and from fornication, and from things strangled, and from blood.
There was a controversy in Jerusalem that most of the Jews were telling the gentiles that in order to be saved, they needed to be circumcised as it is written in the book of Moses. At the height of this debate in the Christian community, Apostle James and Peter and all the other Apostles decided to put an end to the debate, with apostle James writing the verses we read above, and extending all the way through verse 29.
This is the particular epistle that was written by the Apostles in collaboration with one another. This was sent to Antioch, Syria and Cilicia.
In verse 30, the epistle was delivered to the gentiles. This is one true book of the Bible was written by not one particular person but by all the Apostles present, agreed to write this letter to all the gentiles.
They knew that there were 66 books of the Bible but this other book written by the joint effort of all the Apostles, the elders, and the members of the church. This epistle is what Bro. Eli Soriano refers to as the 67th Book Of The Bible.