TT #212 · Parashas Shoftim · Fifth Aliyah · Passuk 19:06
Lest the blood-avenger pursue the killer, because his heart is hot, and overtake him because the way is long, and strike him mortally, though he has no judgment of death, for he was not an enemy to him from yesterday and the day before.
Torah Temimah points to Makkot 10b.
TT lemma: פֶּן יִרְדֹּף גֹּאֵל הַדָּם.
English: ‘Lest the blood-avenger pursue the killer’ – therefore they prepare the roads.
Derash on the motive for road preparation (Bavli) — the danger of pursuit drives the requirement of clear, short routes.
The roads to the cities of refuge are prepared so that the accidental killer is not overtaken by the blood-avenger while his heart is still hot.