Read on Simchat Torah, Where the Cycle Turns

Vezot Haberachah is unique in being read not on an ordinary Shabbat but on the festival of Simchat Torah, when the annual cycle is completed and immediately begun again from Genesis, so that the account of Moses' death is followed at once by the words 'In the beginning.' The custom expresses the tradition's ideal of Torah study as ceaseless, with no true end. The portion's closing tribute names no prophet in Israel since like Moses (34:10).

Simchat Torah itself, the festival on which this closing portion is read, is not a biblical institution: Deuteronomy legislates nothing about it, and the celebration developed only in the early medieval period, when Babylonian Jewish communities of around the ninth and tenth centuries, already keeping an annual reading cycle that finished on the second day of Shemini Atzeret, began marking that day's completion with dancing and rejoicing over the scroll, a practice that had acquired its familiar name by around the eleventh century. The custom of immediately opening a new cycle at Genesis the moment Deuteronomy ends is itself the practical expression of the older rabbinic dictum that Torah study has no true terminus, only a turning. The custom of dancing with the Torah scrolls on Simchat Torah, hakafot, in which the scrolls are carried in joyful circuits around the synagogue, developed alongside the festival itself in the medieval period and is not mentioned in any earlier source describing the completion of the annual reading cycle.