Man wrestling with deity is explosive (8)
I believe the answer is:
dynamite
'is explosive' is the definition.
(dynamite is an explosive)
'man wrestling with deity' is the wordplay.
'wrestling with' is an anagram indicator.
'man' with its letters mixed up with 'deity' can make 'DYNAMITE'.
(Other definitions for dynamite that I've seen before include "Exciting person - explosive" , "Fantastic" , "Spectacular (or dangerous) person (or thing)" , "Jelly" , "Explosive - amazing thing" .)