Doctrine has a male deity returning (5)
I believe the answer is:
dogma
'doctrine' is the definition.
(I know that dogma is a type of doctrine)
'a male deity returning' is the wordplay.
'male' becomes 'm' (common abbreviation).
'deity' becomes 'god' (a deity is a god or divine being).
'returning' says the letters should be written in reverse.
'a'+'m'+'god'='amgod'
'amgod' written backwards gives 'DOGMA'.
'has' acts as a link.
(Other definitions for dogma that I've seen before include "Inflexible doctrine" , "Set of beliefs" , "Authoritative doctrine" , "Belief, precept" , "Doctrine put forward as true, not to be questioned" .)