Tell clergyman not to start (6)
I believe the answer is:
relate
'tell' is the definition.
(as in to tell or relate a story)
'clergyman not to start' is the wordplay.
'clergyman' becomes 'prelate' (prelate is a kind of clergyman).
'not to start' means to remove the first letter.
'prelate' with its initial letter removed is 'RELATE'.
(Other definitions for relate that I've seen before include "Recount" , "Sympathise" , "Narrate in Tralee" , "Tell (a story)" , "Show a connection between (things)" .)