Scholarship on the ethics of war in Islam has been dominated by juridical categories drawn from fiqh al-siyar, centered on jus ad bellum and jus in bello as codified by classical jurists and reconstructed by contemporary comparative ethicists. This article argues that the Islamic mystical tradition (ʿirfān/taṣawwuf) offers a distinct and underexplored contribution to this discourse: not a rival legal code, but an ontological grounding that deepens, and in places narrows, the juridical boundaries of legitimate violence. Drawing on Ibn ʿArabī's doctrine of waḥdat al-wujūd, the Qurʾanic concept of karāmah (inherent human dignity), and the chivalric ethics of futuwwat/jawānmardī, the article shows how mystical metaphysics reframes the human being — friend or foe, combatant or civilian — as a locus of divine self-disclosure whose inviolability precedes and exceeds any juridical classification. This reframing supplies a metaphysical warrant beneath the legal rule for principles such as distinction, proportionality, and non-combatant immunity, addressing the gap between formal rule-following and the interior ethical formation of those who fight. The article also examines the historical ambivalence of mystical fraternities toward violence, cautioning against a romanticized reading of ʿirfān, and proposes a complementary rather than substitutive relationship between Islamic law and Islamic mysticism in reconstructing a contemporary Islamic peace ethic.