tradition - a long time ago, the church assembled some of the writings they found, canonized it, and called it "The Bible". They said "this is the TRUTH because we say so, and God talks to us.
ever since then, people have just assumed that what their parents and grandparents have said is true, without bothering to think for themselves. after all, that is encouraged - as every christian knows, it's GOOD to be a sheep!
