The Bible was passed down verbally, for centuries, before any of the writing was even begun, and those earliest writings had to be copied, from verbal accounts, as the originals are not to be found. The first Bible was compiled in the 4th century, under Constantine 1, the very first Christian emperor, by his council of Carthage. Interestingly, several books of the Bible were left out forever after.
The first book of the Bible, Genesis, was verbally completed about 1271 B.C.E, and the last book, Revelation was completed about the year 96 C.E.
The Bible was passed down verbally, as there was no writing back then, over a period of about 1300 years, beginning with Moses' writing Genesis in the wilderness around 1271 BCE, to John's writings in about 98 CE, and the gospel according to Matthew in the 1st century (which some scholars say probably was not written by Matthew).
Some scholars also feel the Gospel authors copied each other's work to a large extent. Some feel, since Moses displays such horrific morality, that his writings may not have been divinely inspired. One example is Numbers 31:13-18, in which he orders murdering children, and non-virginal women, but advises his soldiers to keep virgin women and female children for themselves.
According to a 2011 Gallup poll..."Three in 10 Americans interpret the Bible literally, saying it is the actual word of God". God help us!
ps...sorry to break the bubble but Jesus wasn't born on Christmas!