Confuse second of judges new on bench (8)
I believe the answer is:
unsettle
'confuse' is the definition.
(thesaurus)
'second of judges new on bench' is the wordplay.
'second of judges' becomes 'u' (end letter of 'judges').
'new' becomes 'n' (abbreviation as in New Testament NT).
'on' means one lot of letters go next to another.
'bench' becomes 'settle' (settle is a kind of bench).
'u'+'n'+'settle'='UNSETTLE'
(Other definitions for unsettle that I've seen before include "worry" , "Nettle us so as to disturb" , "Fluster" , "Upset" , "'Disturb, unnerve (8)'" .)