Good time follows single and double (4)
I believe the answer is:
spit
'double' is the definition.
(as in a 'spitting image')
'good time follows single' is the wordplay.
'good' becomes 'pi' (old-fashioned term for pious).
'time' becomes 't' (abbreviation).
'follows' says to put letters next to each other.
'single' becomes 's' (this might be a standard abbreviation which I don't know about).
'pi'+'t'='pit'
'pit' put after 's' is 'SPIT'.
'and' is the link.
Can you help me to learn more?
(Other definitions for spit that I've seen before include "Large skewer - expel saliva" , "Long, narrow point" , "Skewer; headland" , "Roast turner" , "on the barbecue?" .)