It's from the laity, this song (3)
I believe the answer is:
lay
'this song' is the definition.
(lay is a kind of song)
'it's from the laity' is the wordplay.
'it's' becomes 'it' (I've seen this in other clues).
'from' is a deletion indicator.
'laity' with 'it' removed is 'LAY'.
(Other definitions for lay that I've seen before include "Not ordained; song" , "Of bird, produce egg" , "Air" , "like a minister? On the contrary" , "Set down; song" .)