Songs of praise revealed second thoughts over charity (6)
I believe the answer is:
psalms
'songs of praise' is the definition.
(I've seen this in another clue)
'second thoughts over charity' is the wordplay.
'second thoughts' becomes 'ps' (as in P.S. in a letter).
'over' is a charade indicator (letters next to each other) (in a down clue, some letters go over others).
'charity' becomes 'alms' (alms is a kind of charity).
'ps'+'alms'='PSALMS'
'revealed' acts as a link.
(Other definitions for psalms that I've seen before include "Move fast, noisily" , "Biblical songs" , "Holy songs" , "OT book" , "Sacred songs or hymns" .)