The Pentateuch is most likely the oldest part of the Bible, however there is speculation that the book of Job could be older due to the similarities of Job to the patriarchal period, ie counting wealth in flocks and the sacrifices being performed by the patriarch of the household rather than a priest. Scholars do not know exactly when these books were written however many place Moses at between 1,600 - 1,450 BC. The earliest parts may have been written more than 1,000 years before the final parts according to the Julius Wellhausen 4 JEDP theory. However this theory is based on the idea that the Pentateuch is a disjointed work and has received due criticism. Modern archaeological discoveries suggest that some of the oldest stories in Genesis may date back three thousand years.