Divine messenger's strange email gripping church (7)
I believe the answer is:
michael
'divine messenger's' is the definition.
(Biblical figure)
'strange email gripping church' is the wordplay.
'strange' indicates an anagram.
'gripping' means one lot of letters goes inside another.
'church' becomes 'ch' (common abbreviation).
'email' with letters rearranged gives 'miael'.
'miael' going around 'ch' is 'MICHAEL'.
(Other definitions for michael that I've seen before include "Man" , "- Faraday, English scientist" , "1987 Best Actor Oscar winner for 'Wall Street'" , "Man's name" , "- Faraday, English chemist/physicist" .)