Were the Gospel accounts based on the testimony of eyewitnesses who were still alive when the Gospels were written?

The way the Gospel accounts use the right names for people shows that they were about real people, based on reliable information.

The way the Gospel accounts use correct place names shows that they were based on reliable information from first hand testimony.

This video describes the discovery of the earliest copy of part of John's Gospel, the 'John Rylands Fragment'.

Were the Gospel accounts corrupted as they were passed on? Was there any way to prevent this happening?

This video considers whether we can dismiss the accounts of Jesus's life simply because they describe miracles.

How big are the differences between the hand-written copies of the Gospels' accounts of Jesus? Do these undermine what we can know about…