Like some religious leaders, babble endlessly in upset state? (10)

'like some religious leaders' is the definition.

'babble endlessly in upset state?' is the wordplay.
'babble' becomes 'rabbit'.
'endlessly' means to remove the last letter.
'upset' says the letters should be written backwards.
'state?' becomes 'cal' (I've seen this in other clues**).
'in' in reverse letter order is 'ni'.
'rabbit' with its final letter taken away is 'rabbi'.
'rabbi'+'ni'+'cal'='RABBINICAL'