Or HaChaim on Deuteronomy 30:2/אור החיים על דברים ל׳:ב׳

1 ושבת עד ה׳ אלוקיך, "And you will return unto the Lord your G'd." The expression ושבת is stronger than והשבת אל ללבך, as I explained. The former does not refer to repentance but to a reinforcing of the faulty life-outlook of the sinning Jew who finds himself in exile. The Torah makes this plain by adding the words עד השם.