We listen in hush, she is raving: an opportune time to ... (5,3,3,6)

'we listen' is the definition.
I don't know anything about this answer so I can't judge whether this works.

'in hush she is raving an opportune time to' is the wordplay.
I cannot quite understand how this works, but
'in' is found in the answer.
'hush' could be 'sh' and 'sh' is located in the answer.
an anagram of 'she' is 'hes' which is located in the answer.
'an' could be 'i' (Roman numeral for one) and 'i' is found in the answer.
'time' could be 't' and 't' is found in the answer.
This may be the basis of clue (or it may be nonsense).

Can you help me to learn more?