Converts seek religion, not golf, nursing yen for prayer (5,7)
I believe the answer is:
kyrie eleison
'prayer' is the definition.
(thesaurus)
'converts seek religion not golf nursing yen' is the wordplay.
'converts' indicates anagramming the letters.
'not' suggests deleting specific letters.
'golf' becomes 'g' (phonetic alphabet: alpha, bravo, charlie etc.).
'nursing' means one lot of letters goes inside another.
'yen' becomes 'y' (resembles the symbol for the currency of Japan).
'seek'+'religion'='seekreligion'
'seekreligion' with 'g' taken out is 'seekreliion'.
'seekreliion' with letters rearranged gives 'krieeleison'.
'krieeleison' enclosing 'y' is 'KYRIE ELEISON'.
'for' acts as a link.
(Another definition for kyrie eleison that I've seen is " Opening phrase of Mass".)