Evangelist taking part in scam at the weekend (7)
I believe the answer is:
matthew
'evangelist' is the definition.
(one of the four Christian evangelists)
'part in scam at the weekend' is the wordplay.
'part in' indicates a hidden word.
'MATTHEW' is hidden in the letters of 'scam at the weekend'.
'taking' acts as a link.
(Other definitions for matthew that I've seen before include "Apostle to whom the first Gospel is ascribed" , "religious text" , "Patron saint of tax collectors" , "Boy's name" , "First book of NT" .)