It's wrong to put people through awful pain (7)
I believe the answer is:
torment
'it's wrong' is the definition.
(thesaurus)
'people through awful pain' is the wordplay.
'people' becomes 'men' (men are people).
'through' means one lot of letters goes inside another (inserted letters go through the word).
'awful pain' becomes 'tort' (I can't explain this - if you can you should give a lot more credence to this answer).
'men' placed inside 'tort' is 'TORMENT'.
'to put' is the link.
Can you help me to learn more?
(Other definitions for torment that I've seen before include "Persecute" , "Cause mental distress" , "Hound" , "Harry" , "Severe pain" .)