Clement I has extremes of emotion during religious fast (7)
I believe the answer is:
lenient
'clement' is the definition.
(similar in meaning)
'i has extremes of emotion during religious fast' is the wordplay.
'has' is a charade indicator (letters next to each other).
'extremes of' suggests removing the centre (only the letters at the extremes of the word).
'during' means one lot of letters goes inside another.
'religious fast' becomes 'lent' (Lent is a period of fasting in Christianity. I am not sure about the 'religious' bit.).
'emotion' with its centre removed is 'en'.
'i' after 'en' is 'eni'.
'eni' put within 'lent' is 'LENIENT'.
Can you help me to learn more?
(Other definitions for lenient that I've seen before include "Light" , "Forgiving, soft" , "Soft-hearted" , "'Indulgent, easy (7)'" , "Showing tolerance" .)