Lines of holy men receive halo (7)
I believe the answer is:
strings
'lines' is the definition.
(string is a kind of line)
'holy men receive halo' is the wordplay.
'holy men' becomes 'sts' (i.e. St.'s, saints).
'receive' indicates putting letters inside.
'halo' becomes 'ring' ('ring' can be a synonym of 'halo').
'sts' going around 'ring' is 'STRINGS'.
'of' is the link.
(Other definitions for strings that I've seen before include "Cords" , "Undesirable conditions" , "Just; trade exhibition" , "Orchestral section" , "Lengths of wire etc on a musical instrument" .)