Most people agree that the gospels were written outside of the land in which they took place (Israel/Palastine) and several years after they happened. The original accounts could therefore have changed as they were passed on orally. However, the more that various non essential details of the stories can be verified, the more likely it looks like they stories themselves were not simply made up or embellished over time. This apparently is indeed the case. Take names. If you were making the stories up in another time and place you might use names that reflected your current culture rather then the one 50 years ago in another part of the world. If I were to make up a story about people in France 50 years ago would the names I used be those in use then and if I had hundreds of characters would my choices for names reflect the correct popularity of those names. Turns out that the gospels pass that test and many others. Anyway, here is where I just heard all this:
He gets some of his figures from Jesus and the eye witnesses by Richard Bauckam which I have. Here are some key stats from page 71/72:
Stats are [at the time in the region]/[in the gospels]:
15.6% / 18.2% of men bore one of the two most popular names, Simon and Joseph.
41.5% / 40.3% of men bore one of the none most popular male names
7.9% / 3.9% of men bore a name that is attested only once in [all] our sources
28.6% / 38.9% of women bore one of the two most popular names, Mary and Salome
49.7% / 61.1% of women bore one of the none most popular female names
9.6% / 2.5% of women bore a name that is attested only once in [all] our sources
They are not that different are they? I guess we need to know how the stats changed over time and place though to get an idea of how unlikely it would be for this to happen by chance. Richard Bauckam on page 73 says they were very different, for example the most popular male names in the Diaspora (I think that’s were the early Christians scattered to and wrote the gospels) were things like Eleazat/Lazarus, Sabbataius, Joseph, Dositheus, Pappus, Ptolemaius and Samuel.