Christian missionary isn’t into health resort swindle (5,7)

I believe the answer is:

saint patrick

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'christian' is the definition.
(I know that Saint Patrick is Apostelic Father)

'isn't into health resort swindle' is the wordplay.
'isn't' becomes 'aint' (non-standard version of 'isn't').
'into' indicates putting letters inside.
'health resort' becomes 'spa' (spa can mean a health resort).
'swindle' becomes 'trick' (I've seen this in another clue).
'aint' going into 'spa' is 'saintpa'.
'saintpa'+'trick'='SAINT PATRICK'

'missionary' is the link.
I am not very happy about this link. It may be part of another bit of the clue.

Can you help me to learn more?

I've seen this clue in The Times.

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