Argument backing form of vessel for religious devotion (7)
I believe the answer is:
worship
'religious devotion' is the definition.
(I've seen this before)
'argument backing form of vessel' is the wordplay.
'argument' becomes 'row' (to row is to argue).
'backing' is a reversal indicator.
'form of vessel' becomes 'ship' (I can't explain this - if you can you should believe this answer much more).
'row' backwards is 'wor'.
'wor'+'ship'='WORSHIP'
'for' acts as a link.
Can you help me to learn more?
(Other definitions for worship that I've seen before include "Devotions" , "Religious rites and ceremonies" , "Adoration of a divine being" , "Revere" , "idolisation" .)