Teaching mother to follow pet (5)
I believe the answer is:
dogma
'teaching' is the definition.
(dogma is a kind of teaching)
'mother to follow pet' is the wordplay.
'mother' becomes 'ma' (ma is a kind of mother).
'to follow' says to put letters next to each other.
'pet' becomes 'dog'.
'ma' put after 'dog' is 'DOGMA'.
(Other definitions for dogma that I've seen before include "Set of beliefs" , "fixed opinion" , "Laid-down doctrine" , "Blind faith required" , "Opinion viewed as truth?" .)