Biblical character: Uriah’s first encountered in identical line (6)
I believe the answer is:
samuel
'biblical character' is the definition.
(Old Testament figure)
'uriah's first encountered in identical line' is the wordplay.
'uriah's first' becomes 'u' (1st letter of 'uriah').
'encountered in' means one lot of letters goes inside another.
'identical' becomes 'same' (similar in meaning).
'line' becomes 'l' (used when specifying particular lines from a poem).
'u' going within 'same' is 'samue'.
'samue'+'l'='SAMUEL'
(Other definitions for samuel that I've seen before include "Prophet, anointed King David" , "-- Beckett, Irish dramatist" , "-- Beckett, Irish author" , "Old Testament judge and priest" , "Two books of the Bible bear this name" .)