Working with the church modus operandi -- religious education again (4,4)
I believe the answer is:
'again' is the definition.
'working with the church modus operandi religious education' is the wordplay.
'working' becomes 'on'.
'with' is a charade indicator (letters next to each other).
'the church' becomes 'ce' (abbreviation for Church of England).
'modus operandi' becomes 'mo' (common abbreviation).
'religious education' becomes 're'.
(Another definition for once more that I've seen is " Again".)