Let’s think about what takes place in these gospels. It’s pretty clear though that none of them could possibly have seen all of this.So, one should at least grant that they cannot contain only eyewitness accounts.Let’s first consider whether the gospels contain purely eyewitness testimony. Were the authors in the Garden of Gethsemane when Jesus went off alone to pray?This is surprisingly common, even though the claim can basically be dismissed immediately. Were all four writers present throughout the whole life and ministry of Jesus?The word "Messiah" is an English rendering of the Hebrew word Mashiach, which means "anointed." It usually refers to a person initiated into God's service by being anointed with oil.
All past Messianic claimants, including Jesus of Nazareth, Bar Cochba and Shabbtai Tzvi have been rejected.
Evangelical Christians commonly claim that the gospels were either written by eyewitnesses or the authors had access to eyewitnesses. and the authors were dispersed throughout the region.
Ultimately, these claims are not very convincing to those outside that group. To assume that followers of Jesus would have been in this situation and actually able to read and write is highly suspect.
A common apologist claim is that Mark travelled with Paul and used Peter as a primary source for accounts of Jesus.
We have no real reason to believe this; it is simply later church tradition and it still wouldn’t make Mark an eyewitness.