Esau's father (5)
I believe the answer is:
isaac
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">esau's father</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for isaac that I've seen before include "Son prepared for sacrifice" , "Stern" , "biblical figure" , "Son of Abraham, offered as a sacrifice to God" , "Put away" .)