Comforting word right within you (5)
I believe the answer is:
there
'comforting word' is the definition.
(as in there, there)
'right within you' is the wordplay.
'right' becomes 'r' (common abbreviation).
'within' means one lot of letters goes inside another.
'you' becomes 'thee' (I've seen this in other clues).
'r' going into 'thee' is 'THERE'.
(Other definitions for there that I've seen before include "expression of sympathy" , "Ether (anag)" , "Exclamation of triumph or sympathy" , "on that issue" , "In that location" .)