By: Rabbi Ari Enkin
One will notice that in the course of the Fast Day Torah reading there are verses that are first recited out loud by the congregation which are then repeated by the ba’al koray. This happens during the Kohen aliya with the verse: “shuv m’charon apecha…” and then again in the Yisrael aliya with the verse: “Hashem Hashem…” and the verse “v’salachta l’avoneinu“. However, in the Levi aliya there is no such verse. There is no interaction. There is no audience participation. Why is this?
It is explained that this is because both Kohanim and Yisraelim participated in the sin of the Golden Calf which is from where the Fast Day Torah reading is taken from. It was Aharon, the Kohen Gadol, who actually called for and fashioned the Golden Calf while it was the Yisraelim who worshipped it. The Leviim, however, did not participate in the sin in any way. Therefore, there is no need to emphasize any of the verses of admonishment during the Levi aliya. Indeed, the emphasis and repetition of these verses during the other two aliyot is intended to embarrass the community and stir them to repentance.
See also: Sefer Kushiot #85; Sefer Chassidim #250; Yosef Ometz #47; and Kitzur Shulchan Aruch 78:4 for more on this custom.