Men in extremes of strife flipping love God (4)
I believe the answer is:
eros
'love god' is the definition.
(Greek god of love)
'men in extremes of strife flipping' is the wordplay.
'men' becomes 'or' (military abbreviation for other ranks).
'in' means one lot of letters goes inside another.
'extremes of' means to remove the middle letters (only the letters at the extremes of the word).
'flipping' says the letters should be written in reverse.
'strife' with its middle removed is 'se'.
'or' going within 'se' is 'sore'.
'sore' back-to-front is 'EROS'.
(Other definitions for eros that I've seen before include "God of love; life instinct (Freud)" , "One worshipped" , "Cupid, to the Greeks" , "Winged archer" , "Group of instincts" .)