Truly ruin a schismatic after representing vigorous response to religion (8,12)

I believe the answer is:

muscular christianity

'vigorous response to religion' is the definition.

'truly ruin a schismatic after representing' is the wordplay.
'after representing' is an anagram indicator (the letters presented again in a new way).
'truly'+'ruin'+'a'+'schismatic'='trulyruinaschismatic'
'trulyruinaschismatic' is an anagram of 'MUSCULAR CHRISTIANITY'.

I've seen this clue in The Independent.

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