As far as could be from the Mount of Olives (4)
I believe the answer is:
unto
'as far as could' is the definition.
I know nothing about this answer so I can't judge whether this works.
'from the mount of olives' is the wordplay.
'from' says the answer is hidden in the clue.
'UNTO' can be found hidden inside 'mount of olives'.
'be' is the link.
Can you help me to learn more?
(Other definitions for unto that I've seen before include "'Do ... others, etc.'" , "'The Lord said . . . . Moses'" , "Heading for" , "In the direction of (archaic)" , "Archaic form of to" .)