Comment by vineyardlabs

Questions about authorship aside, note that only Matthew and John claim to be disciples/people who directly interacted with Jesus. Luke is purported to be a physician/associate of Paul who was paid by an unnamed benefactor to document the life of Jesus based on interviews with eyewitnesses and research from earlier sources, and Mark is purported to be writing down an account of the life Jesus based on Peter's eyewitness testimony in Rome several decades after the fact.