Laid back about praying regularly for organ (6)
I believe the answer is:
larynx
'organ' is the definition.
(larynx is a kind of organ)
'laid back about praying regularly' is the wordplay.
'laid back' becomes 'lax'.
'about' indicates putting letters inside.
'regularly' indicates alternate letters (regularly take one letter, leave next etc.).
The alternating letters of 'praying' are 'ryn'.
'lax' enclosing 'ryn' is 'LARYNX'.
'for' acts as a link.
(Other definitions for larynx that I've seen before include "Human voice box" , "box for speaker" , "The formal voice-box" , "Location of vocal cords" , "Cavity containing vocal chords" .)