The faithful priest in the case of Beebe v HM Customs, removing habit (9)
I believe the answer is:
believers
'the faithful' is the definition.
(I've seen this in another clue)
'beebe v hm customs removing habit' is the wordplay.
'beebe' becomes 'belie' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'hm' becomes 'ER' (HM Her Majesty, ER Elizabeth Regina).
'customs' becomes 'ways' (I've seen this in another clue).
'removing' is a deletion indicator.
'habit' becomes 'way' (habit or way of doing something).
'ways' with 'way' taken out is 's'.
'belie'+'v'+'er'+'s'='BELIEVERS'
'priest in the case of' is the link.
This may not be correct. Some or all of it may be part of another bit of the clue.
Can you help me to learn more?