Some quondam Boanerges's stand (4)
I believe the answer is:
ambo
'stand' is the definition.
(thesaurus)
'some quondam boanerges's' is the wordplay.
'some' indicates a hidden word (some parts of the word are used).
'AMBO' can be found hidden inside 'quondam boanerges'.
(Other definitions for ambo that I've seen before include "desk" , "Early form of pulpit" , "Old reading-desk" , "Raised pulpit" , "Early Christian pulpit" .)