Jack found in church, we hear (5)

I believe the answer is:

knave

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'jack' is the definition.
(knave can mean a jack playing card)

I cannot understand how the rest of the clue works.

(Other definitions for knave that I've seen before include "Yet he may be a diamond" , "Jack - rogue" , "Jack - rotter" , "one found amongst thieves" , "Rapscallion" .)

I've seen this clue in The Irish Independent and The Guardian.

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