Origin of the Bible
Investigation of the origin of the Bible can start with The Acts of the Apostles ("Acts"), which is a methodical account of the first Christian church written by a medical doctor named Luke, who served as the assistant to and the note taker for the Apostle Paul.
Acts ends without mentioning Jerusalem being sacked in 70 AD or Nero burning Rome in 64 AD and blaming the fire on Christians to start the great persecution. Since Acts ends with Paul's completion of his 2-year imprisonment in Rome in 62 AD, it most likely was also completed in 62 AD.
Luke begins Acts with, "The former account I made, O Theophilus, of all that Jesus began both to do and teach..." (Acts 1:1)
The "former account" that Luke referred to is what we call today the Gospel of Luke, which was also dedicated to this man named Theophilus: "Inasmuch as many have taken in hand to set in order a narrative of those things which have been fulfilled among us, just as those who from the beginning were eyewitnesses and ministers of the word delivered them to us, it seemed good to me also, having had perfect understanding of all things from the very first, to write to you an orderly account, most excellent Theophilus, that you may know the certainty of those things in which you were instructed." (Luke 1:1-4)
The delivered eyewitness accounts Luke mentions above are what we today call the Gospel of Matthew, written by one of Jesus' twelve Apostles, and the Gospel of Mark, written by the assistant to and the note taker for the Apostle Peter. If we estimate a 3-5 year gap between Acts and the Gospel of Luke and another 3-5 year gap between the Gospel of Luke and the Gospels of Matthew and Mark, this means that three of the four Gospels were written around 52-59 AD, or only about 20 to 30 years after they last saw Jesus.
Some of the other New Testament books were written before and some after these Gospels, but all were written by eyewitnesses of Jesus or their note takers, and read by people who were also eyewitnesses and could validate their details.
Communication was predominantly oral back then. Things tended to be written down when the speakers felt they won't be able to speak about the content for much longer, towards the end of their lives.
Not in this case, for 4 reasons:
1. The modern digital society deluges the human memory with an unprecedented amount of information at an unprecedented speed, but is relatively tolerant of inaccuracies in the information retained since reliable digital copies of the information exist elsewhere. By contrast, oral society of the antiquity didn't deluge the human memory with such information overload, but was also intolerant of inaccuracies in it. Modern standards of recollection cannot be imposed on the oral society of the antiquity.
2. The Gospels didn't record their recollection of things that happened 20 to 30 years earlier and then hadn't been revisited until 20 to 30 years later. The Gospels recorded what they had been talking about everyday during those 20 to 30 years. The recorded content wasn't 20 to 30 years years old; it had been kept fresh for 20 to 30 years.
3. The events recorded weren't mundane everyday affairs. They were astounding miracles and incidents that defined history. Imagine you had been next to the US President John F. Kennedy's slow moving limousine when he was shot. Even in a digital society, wouldn't you clearly remember what you witnessed even after 20 to 30 years?
4. The people who listened to the Apostles during those 20 to 30 years and read the Gospels after they were written included many who also had witnessed the spoken and written content, and they confirmed the accuracy of what the Apostles said and wrote or had written.
Some claim that the Council of Nicea "picked" the books to be included in the New Testament. This is false. That council, convened in AD 325 by Constantine - the newly minted "Christian" emperor - merely affirmed for the emperor's new official purposes what had already been recognized as the New Testament for two hundred years. The four Gospels, for example, were stitched together as early as the first century AD to distinguish them from the many dubious writings that already tried to parade as Gospels inspired by God.
The New Testament was closed in late 1st century AD when John, the last surviving Apostle, closed the last book of the Bible with the following stern warning: “For I testify to everyone who hears the words of the prophecy of this book: If anyone adds to these things, God will add to him the plagues that are written in this book; and if anyone takes away from the words of the book of this prophecy, God shall take away his part from the Book of Life, from the holy city, and from the things which are written in this book." (Revelation 22:18-19)
Recognizing a writing as the Word of God wasn’t done on someone’s whim or personal preference, but based on whether or not it met the criteria of “canon”: the writer had to have been one of Jesus' Apostles or their note taker, the writer at least had to claim to have written from divine inspiration (which then needed to be confirmed), and the content could neither contradict what had already been recognized as the Word of God nor contain other errors.
For example, contrast John’s closure in Revelation above with Macabees’ closure of Macabees 2: “If it is well told and to the point, that is what I myself desired; if it is poorly done and mediocre, that was the best I could do.” Since the author doesn’t even claim divine inspiration, there is no need to confirm it.
Or consider the following verses from the so called “gospel” of Thomas, one of the many writings that various people, cults and sects through the centuries have put forth as “lost” or “newly discovered” word of God: “Simon Peter said to them, "Make Mary leave us, for females don't deserve life." Jesus said, "Look, I will guide her to make her male, so that she too may become a living spirit resembling you males. For every female who makes herself male will enter the kingdom of Heaven." (Gospel of Thomas 114) “Jesus said, "Lucky is the lion that the human will eat, so that the lion becomes human. And foul is the human that the lion will eat, and the lion still will become human." (Gospel of Thomas 7) The only thing such writings call into question is the mental soundness of their proponents.
The New Testament was originally written in Greek. The earliest Greek manuscripts of the New Testament discovered date to about three centuries after Christ, and the number of ancient Greek manuscripts or fragments of the New Testament discovered to date exceeds 5,600.
Two things can be said about this. Firstly, what we know about the history of the Roman Empire is based largely on The Annals of the Roman Empire, written by the Roman historian Tacitus in 116 AD. There are only two manuscripts in the world of that in the original language. One dates from the 9th century and the other dates from the 11th century. Therefore, the details about the history of the Roman Empire stand on two manuscripts written about 1000 years after the original, while the details about the Bible stand on over 5,600 manuscripts that date from about 300 years after the originals. In other words, there is far stronger written evidence for the Bible than for the history of the Roman Empire.
Secondly, these 5,600+ manuscripts of the New Testament in the original Greek were discovered over a vast geographic area that stretches from the Middle East to Ethiopia, Spain, Ireland and Germany. Imagine a kindergarten class playing a game of whisper telephone. The teacher whispers, "Johnny played with Laura near the swings yesterday" to two children, and they each whisper to two other children, and so on. If after ten generations, a child at one corner of the room reports, "Johnny played with Laura near the swings yesterday," while a child at another corner reports, "Johnny fought with Laura on the swings" the children won’t know what the teacher had whispered originally. But if the two children at the distant corners say exactly same thing, the original message can be deduced without having been heard by all.
What's the point? The copies of the Gospels penned by Matthew, Mark, Luke and John have not been and most likely will never be found since they most likely disintegrated long ago from having passed from hand to hand to be read and copied. But almost all (95-99%) of the 5,600+ manuscript copies all say in effect, "Johnny played with Laura near the swings yesterday." So we can deduce that what was originally penned is what is in those 5,600+ copies.