Song for that man on the radio (4)
I believe the answer is:
Here is my best explanation:
'song' is the definition.
'that man on the radio' is the wordplay.
'that man' becomes 'him' (I've seen this before).
'on the radio' indicates a 'sounds like' (homophone) clue.
'him' is a homophone of 'HYMN'.
'for' is the link.
(Other definitions for hymn that I've seen before include "Song in praise of 22 down", "Psalm", "religious works", "Praise", "religious composition", "One sung in church", "Orison", "Religious song of praise", "sort of song" and "Anthem".)