Balance affected manner with righteous heart (7)
I believe the answer is:
remnant
'balance' is the definition.
(thesaurus)
'affected manner with righteous heart' is the wordplay.
'affected' is an anagram indicator.
'with' means one lot of letters go next to another.
'heart' says to take the centre.
The middle letter of 'righteous' is 't'.
'manner' is an anagram of 'remnan'.
'remnan'+'t'='REMNANT'
(Other definitions for remnant that I've seen before include "Piece of leftover fabric" , "Men rant poorly when it's left over" , "Scrap" , "Small amount (esp. cloth) left" , "rest" .)