The first book of the Old Testament (7)
I believe the answer is:
genesis
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">the first book of the old testament</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for genesis that I've seen before include "rock group" , "Origin -- see sign (anag)" , "Beginning (in the Bible)" , "Origin; Bible book" , "Bible's first book" .)