Evangelist after getting into booze (7)
I believe the answer is:
apostle
'evangelist' is the definition.
(I've seen this in another clue)
'after getting into booze' is the wordplay.
'after' becomes 'post' (prefix meaning after, eg post-war).
'getting into' means one lot of letters goes inside another.
'booze' becomes 'ale' (type of alcohol).
'post' going inside 'ale' is 'APOSTLE'.
(Other definitions for apostle that I've seen before include "Augustine, say" , "Leaps to find religious follower" , "Disciple of Jesus Christ" , "E.g. St Paul" , "Holy person" .)