After presenting B'nei Yisroel with a tochacha (admonition) about the future golus (exile), followed by teshuva (repentance) and ge'ula (redemption), Moshe Rabbeinu appears to unexpectedly and radically 'switch gears' in his delivery, as we read: 'Then Moshe designated three cities (of refuge) on the east side of the Yarden (Jordan River), for an unwitting killer to flee...' (Devarim 4:41-42) Following Moshe's designation of Arei Miklat (Cities of Refuge), he resumes his messages about heeding Hashem's mitzvos.

The obvious question is why Moshe suddenly designates Arei Miklat at a juncture which is seemingly totally unrelated to the context. This question appears to have bothered the commentators (see Rashi, Ramban, Ibn Ezra and S'forno); I'd like to suggest an alternative approach.

Parshas Va'eschanan is unique in that its tochacha contains the concept of teshuva. Whereas previous admonitions warned about the consequences of sin, the tochacha of Va'eschanan introduces teshuva as the key to reverse these consequences.

Teshuva is a very difficult concept for the human mind to process and accept, for teshuva precipitates atonement and can even erase sin, defying our sense of logic.

This is precisely why Moshe designated Arei Miklat immediately after delivering his admonition. Killing another person is among the most severe sins in the Torah, and it is surely irreversible. For this very reason did Moshe elect to designate Arei Miklat as a postscript to his tochacha, in order to illustrate the potency of teshuva; for the unwitting killer - who committed a severe, irreversible sin - is granted atonement upon the completion of his term in Arei Miklat (see Rambam Hil. Rotze'ach 7:14), powerfully demonstrative of the great, challenging concept of teshuva.

If one who takes human life can obtain atonement for his deed, all the more so should we be inspired to engage in teshuva with the confidence that its transformative qualities can enable us to change our spiritual paths and directions for the better.