The victory of Iran’s Islamic Revolution in 1979 marked an epistemological rupture in the prevailing paradigms of public administration and the political sociology of development. At the core of this new configuration, the concept of "social justice" was established—not merely as a palliative welfare policy or a propaganda slogan, but as a central signifier and the philosophical basis for the political legitimacy of the system—thereby delineating its conceptual boundaries against rigid socialist egalitarianism and the formalistic liberty of liberalism. Employing an approach that traces epistemological lineage alongside a descriptive-analytical method, this study examines the origins of the concept of justice within the intellectual frameworks of two leading theorists of the Islamic Revolution—Imam Khomeini and Professor Morteza Motahhari—and elucidates its structural implications for the reproduction of "social capital" and the quality of "political participation." The findings indicate that Motahhari—drawing upon the theological foundations of the *Adliyya* school, Shi'a rationalism, and an emphasis on innate rights—establishes a model of "procedural and merit-based justice." The sociological outcomes of this model include the generation of institutional trust and structural discipline, the strengthening of bridging social capital, and the elevation of political participation to a level that is civic, institutionalized, and rational. In contrast, taking "engaged mysticism" (or "applied spirituality"), a purpose-oriented jurisprudence of governance, and the Quranic dichotomy of the "oppressed versus the arrogant" as his starting points, Imam Khomeini emphasizes "