This paper offers a socio-theological reflection on the relationship between ethos-arché and liberation as key categories for a critical understanding of social (in)justice from an interreligious perspective. It begins from the premise that social injustice cannot be understood solely in economic, political, or institutional terms, since it also reveals a deeper rupture in the ethical and spiritual dimensions of human existence. In this sense, ethos-arché is approached not simply as an ontological principle, but as a grounding principle for understanding human dignity, relationality, and ethical responsibility. The category of liberation helps clarify the tension between the original ethical impulses preserved within religious traditions and the historical processes through which these traditions may also become entangled in asymmetries of power, exclusion, and the legitimation of inequality. With primary reference to Christianity and Buddhism, especially to the ethical and humanizing significance of the praxis of Jesus and to Buddhist understandings of suffering, interdependence, and compassion, the paper also opens a broader interreligious horizon by arguing that different religious traditions preserve moral and spiritual resources for confronting suffering, dehumanization, and structural injustice. It argues, therefore, that a theological critique of social injustice requires both the recovery of the ethical core of religious traditions and interreligious dialogue that fosters mutual accountability, shared responsibility, and concrete engagement in the face of injustice. Keywords Ethos-Arché; Liberation; Christianity; Buddhism; Theological critique; Interreligious perspective.