No part of history has come down to us so well attested as the life of our Lord and Savior Jesus Christ. A man believes what Tacitus tells him, although very likely Tacitus did not see the things and only got them secondhand. But as a reputable historian, his witness is received.
Surely the witness of Matthew, Mark, Luke, and John, and Peter, and James, and Paul, is as good as the witness of Julius Caesar or Tacitus. It is rendered more trustworthy from the fact that they died for adhering to it, which neither Caesar nor Tacitus were made to do.