Gather together for a church service (5)

I believe the answer is:

amass

'gather together' is the definition.

'a church service' is the wordplay.
'church service' becomes 'mass' (I've seen this before).
'a'+'mass'='AMASS'

'for' is the link.

(Other definitions for amass that I've seen before include "Stockpile" , "Sodium chloride" , "Accrue, heap up" , "Collect, hoard" , "Accumulate over time" .)

I've seen this clue in The Telegraph.

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