Disturbing sermon with bit concerning one of hell's torments (9)
I believe the answer is:
brimstone
'one of hell's torments' is the definition.
'disturbing sermon with bit' is the wordplay.
'disturbing' is an anagram indicator (I've seen this in other clues).
'with' means one lot of letters go next to another.
'sermon' after 'bit' is 'bitsermon'.
'bitsermon' with letters rearranged gives 'BRIMSTONE'.
'concerning' is the link.
(Other definitions for brimstone that I've seen before include "Yellow butterfly" , "hellish punishment" , "Old name for sulphur" , "Sulphur; butterfly" , "Biblical sulphur that rained with fire on evil cities" .)