The issue of war and the determination of its moral boundaries have always been fundamental challenges in the political theology of religions. The present study aimed to conduct a comparative analysis of the theological and epistemological foundations of civilian immunity in armed conflicts from the perspective of the Old Testament theology and Imami theology (manifested in the military Seerah of Imam Ali, peace be upon him). Employing a qualitative, descriptive-analytical method and a comparative theological approach, this study examined library data extracted from the Old Testament texts (focusing on the Books of Deuteronomy and Joshua) and the Nahj al-Balagha. The findings revealed that the military approach in certain Old Testament battles was based on the theological doctrine of "Herem" (total destruction) and the "Divine Command Theory," where God's will is not constrained by human perceptions of justice, thus providing theological justification for the annihilation of civilians to preserve the purity of the chosen people. In contrast, the military Seerah of Imam Ali (AS) was founded upon the theological doctrines of "inherent rational good and evil" and "Divine Justice." Accordingly, the life of a civilian, regardless of their beliefs, was considered to possess inherent dignity and absolute immunity. It was concluded that the disparity in the military conduct of these two traditions towards civilians was not merely a jurisprudential or historical difference; rather, it was rooted in the confrontation of two distinct epistemological systems: an exclusionary and ethnocentric theology versus a justice-oriented and dignity-based theology.