||Actually, at first Christians did not have a written body of doctrine; most Christian thought at the time was passed by word-of-mouth. Eventually, some people started writing down Christian stories that they were told; at the influence of Christianity and worldwide literacy increased, the number of such works grew tremendously. At one time, there were thousands of Christian texts in existence -- virtually every community seemed to have their own, unique Christian text. The diversity was very wide, and some works were downright heretical and untrue. At one point, when the amount of disinformation became daunting to ordinary Christians. Something had to be done -- a committee of prominent Christian thinkers was put together, to decide which texts were authentic. Texts were judged by historical and dogmatical validity -- meaning that if a text could not prove its own historical origins, it was rejected, even if it did not contain heretical fallacies. Eventually, after quite a bit of deliberation, the current New Testament was put together. Everything that was rejected became the apocrypha. Some of it survives to this day, and makes quite interesting reading. Don't take it too seriously, though, or at least consult your pastor first -- some (but not all!) is heretical or downright stupid.
P.S. Interesting moment: The most contentious book the New Testament was the Apocalypse of St. John; it just barely made it into Christian canon, with a large and active minority against it. (Which, incidentally, is why it is last in the Bible.) Those against including it thought that many narrow-minded people would take it too literally; seems they were right. People get dumber with centuries, and what was once quite obviously allegory and metaphor is now taken at face value. Sad.
Peace and much love...