Messenger has job getting in beer (7)
I believe the answer is:
apostle
'messenger' is the definition.
(I've seen this before)
'job getting in beer' is the wordplay.
'job' becomes 'post' (post is a kind of job).
'getting in' indicates putting letters inside.
'beer' becomes 'ale' (I've seen this before).
'post' placed inside 'ale' is 'APOSTLE'.
'has' acts as a link.
(Other definitions for apostle that I've seen before include "One of Christ's 12 original disciples" , "Missionary or evangelist" , "Follower of Christ" , "Leaps to find teacher of faith" , "A follower of Jesus" .)