Source: Mishnah Yoma 3:8; 4:2; 6:2; Talmud Bavli Yoma 36b, 87b; Seder Rav Amram (~860 AD); Maimonides, Hilchot Teshuvah 2:3.

Verbal confession (vidui) is the most essential component of teshuvah per Maimonides. The High Priest’s three Yom Kippur confessions become the model for public Ashamnu and Al Chet prayers — plural (‘we have sinned’), emphasizing communal accountability. Maimonides (Hilchot Teshuvah 2:3): ‘One who confesses verbally but does not resolve to abandon the sin is like one who immerses in a mikveh while holding a dead reptile.’ Confession without transformation is null.