The Adjuration of Imam Ali (PBUH) in the Six-Member Council is one of the most pivotal texts in the history of Islamic political thought, wherein the issue of leadership legitimacy is juxtaposed against the traditional structure of consultation. Transcending a mere personal defense, this adjuration constitutes a foundational act to critique the existing power structure and propose an alternative model in Islamic political thought. In this model, legitimacy is redefined not on the basis of elite consensus, but rather grounded in historical evidence and the Prophetic text (Nass). Drawing on Norman Fairclough’s three-dimensional model (description, interpretation, and explanation), this study employs Critical Discourse Analysis to investigate the redefinition of politico-religious legitimacy and identify the linguistic strategies utilized in the Council's adjuration. The findings reveal that at the descriptive level, Imam Ali (PBUH) employs strategies such as the repetition of divine oaths ("I adjure you by Allah"), a coercive question-and-answer structure, and the contrast of exclusive pronouns, specifically "fīkum" (in you) versus "ghayrī" (other than me). At the interpretive level, these linguistic mechanisms create a space for a moral tribunal and exert social pressure to elicit a collective admission ("They said: O Allah, no") from the political elites present in the Council. At the explanatory level, this speech act, functioning as a discourse of resistance, shifts the intellectual paradigm of legitimacy from "customary-tribal election" to "divine appointment based on merit."