Incredibly modest, this group of Christians (10)

I believe the answer is:

methodists

'group of christians' is the definition.
(Christian denomination)

'incredibly modest this' is the wordplay.
'incredibly' indicates anagramming the letters.
'modest'+'this'='modestthis'
'modestthis' is an anagram of 'METHODISTS'.

(Another definition for methodists that I've seen is " Worshippers".)

I've seen this clue in The Guardian.

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