Porter securing job for messenger (7)
I believe the answer is:
apostle
'messenger' is the definition.
(I've seen this before)
'porter securing job' is the wordplay.
'porter' becomes 'ale' (I've seen this in other clues).
'securing' indicates putting letters inside.
'job' becomes 'post' (post is a kind of job).
'ale' placed around 'post' is 'APOSTLE'.
'for' acts as a link.
(Other definitions for apostle that I've seen before include "Originally, one sent to preach the gospel" , "John, perhaps" , "Principal champion" , "Peter, perhaps" , "Religious messenger" .)