Lest the avenger of blood pursue the slayer,.... These words are to be connected with Deu 19:3, where it is ordered to prepare the way to the cities of refuge, and to divide the land into three parts, for the convenience of the slayer to flee thither, lest he that was next of kin, and incensed against the slayer, and determined to avenge what was done, should pursue after him: while his heart is hot; by reason of the loss of his relation, upon which his passions being raised, his heart becomes inflamed with wrath and anger; which pushes him upon an eager and hasty pursuit of the slayer, before he sits down and coolly considers and deliberates on the affair: and overtake him, because the way is long, and slay him; wherefore it was proper that everything should be done to make the way to these cities as easy and as short as it could be: whereas he was not worthy of death; had not committed an action deserving of it, it being done ignorantly and without notice, as follows: inasmuch as he hated him not in time past; See Gill on Deu 19:4.