The Bible as we know it today developed over a long period of time and was originally transmitted orally before it was finally written down. The entirety of the Bible was written approximately between the years of 1200 BC and 100 AD.
The Old Testament
What Christians refer to as the “Old Testament” is essentially an ancient compilation of the Jewish Sacred Scriptures, the Tanakh — the Hebrew Bible. These holy texts (the Torah, the books of the Prophets, and the “Writings”) developed over time and were at first handed over orally from one generation to the next until they were finally written down and preserved.
Most scholars agree that the Old Testament was written between the years of 1200 and 165 BC.
The New Testament
The New Testament, including the Gospels and the various letters that are included in it, was initially handed on orally, before being written down.
Various writers wrote down in the years following Jesus’ death the many stories circulating about the Messiah. These writers were either apostles or friends of apostles who knew Jesus very well. They witnessed the events or interviewed people who had, and sought to preserve the life and teachings of Jesus Christ in written form.
It is generally believed that the New Testament was written between the years of 50 and 100 AD.