Prophet having Sheila converted (6)
I believe the answer is:
elisha
'prophet' is the definition.
(Hebrew prophet)
'sheila converted' is the wordplay.
'converted' indicates anagramming the letters.
'sheila' is an anagram of 'ELISHA'.
'having' acts as a link.
(Other definitions for elisha that I've seen before include "Hebrew prophet" , "Elijah's successor" , "Prophet; Thirteen across (anag.)" , "Old Testament prophet" .)