This argument is a little technical so bear with me. Because of the high volume of sepulchre inscriptions that have come down to us we now know naming trends in and around first century Judea. Think of it like this, in the modern day we can know how popular the name Mohamed is here in the UK. This material in the United Kingdom is in reverse because we know these names largely by birth records, not so much by who’s expired or by gravestones, the principals aren’t so different either way. To go through a cemetery makes this argument very real to me.
Still returning to first century Judea, by use of tombs and their inscriptions we’ve catalogued names as often as they appear to gain a measure of name popularity. For example Simon, largely because it could be thoroughly Jewish while overlapping with the dominant invading culture that occupied the land, was the most popular Jewish name. One of every four women were given the name Miriam in first century Judea (the source from where we transliterate the name Mary). So of the names we read and name ratio present in both the New testament gospels and the naming of the general populous outside the Bible in the first century, if there’s no overlap of the former with the latter, scholars should suppose the authorship of the New testament gospels having been composed by someone removed from the proper first century context. This is so important because it’s the very context in which Christians and unbelievers have recorded Jesus as having lived and taught.
If the New testament writers haven’t recorded similar names to those of the inhabitance of first century Judea that doesn’t go so far as to disprove their histories, it would raise an awkward question of authenticity for Bible believing Christians nonetheless. The gospel accounts, if having recorded alien names or things which evidently didn’t feature prominently in the context where they’re said to take place, would be an embarrassing thing given scholarly movements like the Jewish reclamation of Jesus etc. To see this argument outlined by a professional I’m going to recommend Richard Bauckham’s book Jesus and the eyewitnesses.
Still let’s jump to the grand finale. Our conclusion is that if the gospels were indeed written by eyewitnesses then the naming ratio that appears in the Bible should be similar to that of the names on the grave sites in first century Judea, and after cataloguing these names in painstaking detail we can say they match, the gospels and first century naming trends are in harmony. Really taking time to reflect on the argument can drive home how powerful it is.
Now this doesn’t guarantee we’re reading eyewitness testimony when we open the New Testament today (Luke wasn’t an eyewitness to Jesus and writes this information freely), though what we can be sure of is that certain books or source material for the books of the New Testament were composed by people in the right place at the right time to be bonafide eyewitnesses to the life, death and resurrection of Jesus. So yes, we can say confidently that the weight of the evidence falls on eyewitness authorship in the New Testament. The New Testament appears to have been written by eyewitnesses, as Christians have believed all along.
― Ty Cormack