Gather confession from fool (5)
I believe the answer is:
amass
'gather' is the definition.
(amass can mean to collect or gather)
'confession from fool' is the wordplay.
'confession' becomes 'am' (I can't explain this - if you can you should believe this answer much more).
'from' is a charade indicator (letters next to each other).
'fool' becomes 'ass' (both can mean a stupid person).
'am'+'ass'='AMASS'
(Other definitions for amass that I've seen before include "Accrue, heap up" , "Accumulate, heap up" , "Get together" , "run up?" , "Accumulate over time" .)