The Bible is one of the world's oldest books. Its oldest sections were written about 1500 years before the birth of Christ. Even its newest sections were written about 1900 years ago.
Clearly, then, having been written over a period of about 1600 years, the Bible was not written by one person. No one knows precisely how many people contributed to the Bible. It is estimated there were about forty authors.
One of the most important facts about the Bible is that those who wrote it did not claim to be the source of the ideas they wrote about. Sometimes directly, sometimes indirectly, the authors assert that what they were writing really came from God. For example, one of the writers, Paul, made this statement: All Scripture [i.e., the Bible] is given by inspiration of God, and is profitable for doctrine, for reproof, for correction, for instruction in righteousness; that the man of God may be perfect, thoroughly furnished unto all good works.` (2 Tim. 3:16-17). Another writer, Peter, wrote: ... For the prophecy came not in old time by the will of man; but holy men of God spake as they were moved by the Holy Ghost (2 Pet. 1:21). Other Bible writers confirm the statements of Paul and Peter.