I do religious painting (4)

I believe the answer is:

icon

'religious painting' is the definition.
(I've seen this before)

'i do' is the wordplay.
'do' becomes 'con'.
'i'+'con'='ICON'

(Other definitions for icon that I've seen before include "Image or figure venerated as sacred" , "Holy image or symbol on computer screen" , "Devotional painting" , "Devotional image (C, not K)" , "Sprites" .)

I've seen this clue in The Telegraph.

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