Richard admitting sin as another man (7)
I believe the answer is:
derrick
'another man' is the definition.
'Derrick' can be an answer for 'man'. I am unsure of the 'another' bit.
'richard admitting sin' is the wordplay.
'richard' becomes 'dick' (I can't justify this - if you can you should believe this answer much more).
'admitting' means one lot of letters goes inside another (admit can mean to welcome in or accept).
'sin' becomes 'err' (to sin is to err morally).
'dick' enclosing 'err' is 'DERRICK'.
'as' is the link.
Can you help me to learn more?
(Other definitions for derrick that I've seen before include "Lifting device" , "Frame over an oil well" , "boy" , "Kind of crane" , "Tower over a borehole" .)