Realise some believer's in pain (7)
I believe the answer is:
achieve
'realise' is the definition.
(I've seen this in another clue)
I cannot understand how the rest of the clue works.
Can you help me to learn more?
(Other definitions for achieve that I've seen before include "Manage to get" , "Consummate" , "Bring about, accomplish" , "Accomplish, gain by effort" , "succeed" .)