Coins to drop in church (6)
I believe the answer is:
change
'coins' is the definition.
(change can mean coins)
'drop in church' is the wordplay.
'drop' becomes 'hang' (hanging is a kind of dropping).
'in' indicates putting letters inside.
'church' becomes 'CE' (abbreviation for Church of England).
'hang' inserted within 'ce' is 'CHANGE'.
'to' is the link.
(Other definitions for change that I've seen before include "Alter with loose coins" , "Coins of low value" , "protean" , "difference" , "Transfer" .)