Religious office lifting financial restriction is limited by income (6)
I believe the answer is:
papacy
'religious office' is the definition.
(office or responsibilities of the pope)
'lifting financial restriction is limited by income' is the wordplay.
'lifting' says the letters should be written backwards.
'financial restriction' becomes 'cap' (eg a cap on expenses).
'is limited by' means one lot of letters goes inside another (limit can mean to contain or border off).
'income' becomes 'pay' (income from a job).
'cap' backwards is 'pac'.
'pac' placed inside 'pay' is 'PAPACY'.
(Other definitions for papacy that I've seen before include "Office of Pope" , "clerical office" , "religious role" , "high church job" , "Vatican leader's office" .)