It's true, I tell tales to keep son in worship (7)
I believe the answer is:
idolise
'worship' is the definition.
('worship'->'idolize' is in my internal thesaurus and 'ize'->'ise')
'it's true i tell tales to keep son' is the wordplay.
'it's true i' becomes 'ido' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'tell tales' becomes 'lie' (I've seen this before).
'to keep' is an insertion indicator.
'son' becomes 's'.
'lie' enclosing 's' is 'lise'.
'ido'+'lise'='IDOLISE'
'in' is the link.
Can you help me to learn more?
(Other definitions for idolise that I've seen before include "Revere (someone) greatly or excessively" , "Worship and adore" , "Make into a figure of worship" , "Worship to extremes" , "Love too much" .)