Suffered from pain delivering Christian treatise (7)

I believe the answer is:

didache

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'christian treatise' is the definition.
I don't know anything about this answer so I cannot tell whether it can be defined by this definition.

'suffered from pain' is the wordplay.
'suffered from' becomes 'did' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'pain' becomes 'ache' (ache is a kind of pain).
'did'+'ache'='DIDACHE'

'delivering' acts as a link.

Can you help me to learn more?

I've seen this clue in The Independent.

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