Commento su Deuteronomio 19:3

תכין לך הדרך THOU SHALT PREPARE THEE A WAY — “Refuge!” "Refuge!" was inscribed at each crossroad (to point the way to the nearest city of refuge) (Makkot 10b).

ושלשת את גבול ארצך, “you shall divide the territory of your land into three sections.” The simile continues, i.e. in order to make a total of six cities of refuge together with the three on the east bank; they are to correspond to the six extremities in our universe. The author understands this division in terms of the three parts of the universe we described earlier. The celestial regions are perceived as the topmost of these three parts of ארצך. Having attained that level in his penitence, the unintentional killer will begin his ascent to spiritual rehabilitation. This is the meaning of והיה לנוס שמה כל רוצח, the letters of the tetragrammaton are perceived as “open” letters, allowing easy access for the fleeing killer. [I believe the whole allegorical approach is based on the fact that this legislation had been spelled out in Numbers 35,9-34. The author may feel that the repetition is meant to allude to the mystical element of how it is possible to completely rehabilitate oneself for killing a person seeing one cannot bring him back to life. Ed.]

At every fork in the road. So that he does not err at the fork in the road.