NumNm. NumbersNúmeros, chaptercapítulo Book of NumbersLibro de los Números, chaptercapítulo 35

But if the slayer shall at any time come without the border of the city of his refuge, to which he was fled;

And the revenger of blood find him without the borders of the city of his refuge, and the revenger of blood kill the slayer; he shall not be guilty of blood: