Curious, most of the biblical scholars I have read are of the opinion that Mark is the oldest and probably the only gospel to have been written by a contemporary of Jesus and also a witness to some of the events.
Most also believe that the other gospels were largely based of the Gospel of Mark.
“Mark is the oldest and probably the only gospel to have been written by a contemporary of Jesus and also a witness to some of the events. “
Why? I don’t know. I’m just standing by, with popcorn.
Papias claimed that Mark had been Peter’s follower and amanuensis. Which leads to the proposition that Mark’s Gospel is based upon Peter’s own account of the events.
Papias is known to us through Irenaeus and Eusebius. Papias is reputed to have known the disciples of the Apostles, and perhaps John himself.