Harmful step I took wrongly at fasting time (9)
I believe the answer is:
pestilent
'harmful' is the definition.
(similar in meaning)
'step i took wrongly at fasting time' is the wordplay.
I cannot quite understand how this works, but
an anagram of 'step' is 'pest' which is present in the answer.
'i' is found in the answer.
'fasting' could be 'lent' (Lent is a period of fasting in Christianity) and 'lent' is present in the answer.
This accounts for all the letters.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for pestilent that I've seen before include "Annoying" , "Mischievous" , "Lets pet in and it becomes harmful to health or life" , "I lent pets that were noxious" , "Vexatious" .)