It was generally admitted that the earth was about four thousand years old at the birth of Christ, but, so careless had Europe been in the study of its annals, that not Until A.D.627 had it a proper chronology of its own.

A Roman abbot, Dionysius Exiguus, or Dennis the Less, then fixed the vulgar era, and gave Europe its present Christian chronology.
The method followed in obtaining the earliest chronological dates was by computations, mainly founded on the lives of the patriarchs.

Much difficulty was encountered in reconciling numerical discrepancies.

Even if, as was taken for granted in those uncritical ages, Moses was the author of the books imputed to him, due weight was not given to the fact that he related events, many of which took place more than two thousand years before he was born.

It scarcely seemed necessary to regard the Pentateuch as of plenary inspiration, since no means had been provided to perpetuate its correctness.