For more information about the OT I will mention a few more things then I will move on with the NT.
The WT and other religions claim that Moses wrought the Pentateuch, there is absolutely no proof for this claim, there is actually a lot of proof against it. First like Leolaia said
Of course Moses did not write the Pentateuch in the sixteenth century BC. If he had, it wouldn't have been written in Hebrew -- it would have been written in an older Canaanite dialect closer to Ugaritic or Amarna Canaanite. The language contains unmistakable signs of a later age. As just one example, the Song of the Sea in Exodus 15 is written in a far more archaic dialect (Early Biblical Hebrew) than the surrounding narrative which was written in Classical Biblical Hebrew. The poem is thought to date to the twelfth century BC, whereas the narrative dates to a time about 500 or 600 years later. That they belong to different eras is plain from the fact that the redactor places the poem on Moses' mouth. He does this because he misinterprets the yiqtol verb tenses as predicting the conquest of Canaan as lying in the future. But the archaic preterite yiqtol verbs in the poem were more like those in Ugaritic and referred to the conquest of Canaan as a past event (in Classical Biblical Hebrew, yiqtol is a jussive/imperfect whereas the preterite forms became prefixed with way-). So Moses did not write the Song of the Sea (which belongs to the period of the judges), and the author who inserted the poem into the text could not have been Moses either.
There is also proof in the verses of the bible itself, for example the books that are claimed to be written by Moses are in the third person when it mention Moses, then there is this verse
Genesis 36:31 (New International Version)
31 These were the kings who reigned in Edom before any Israelite king reigned. and this one
Numbers 12:3 (New International Version)
3 (Now Moses was a very humble man, more humble than anyone else on the face of the earth.)
And this one
Deuteronomy 34:5 (New International Version)
5 And Moses the servant of the LORD died there in Moab, as the LORD had said.
Now these verses were clearly written years after Moses ( if he realy existed ) death.
I await your comments.