Matthew, Mark, Luke or John (7)
I believe the answer is:
apostle
'matthew mark luke or john' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for apostle that I've seen before include "Religious messenger" , "Follower of Christ" , "John, perhaps" , "Preacher perhaps" , "Luke or John, say" .)