Medic losing a love, considering everything mostly as a matter of faith (9)
I believe the answer is:
doctrinal
'a matter of faith' is the definition.
I can't tell whether this definition defines the answer.
'medic losing a love considering everything mostly' is the wordplay.
'medic' becomes 'doc' (doctor).
'losing a love' becomes 'tr' (I can't justify this - if you can you should give a lot more credence to this answer).
'considering everything' becomes 'in all' (I've seen this in another clue).
'mostly' means to remove the last letter (most but not all of the word).
'inall' with its last letter taken off is 'inal'.
'doc'+'tr'+'inal'='DOCTRINAL'
'as' is the link.
Can you help me to learn more?
(Another definition for doctrinal that I've seen is " Relating to beliefs".)