Despite the proliferation of digital communications, modern societies are grappling with the existential crisis of the "epidemic of loneliness" and social atomization. While secular sociology and psychology often approach this crisis through the management of social capital or clinical interventions, the current study aims to provide a fundamental alternative by elucidating the Islamic concept of Uns (spiritual intimacy/fellowship). Employing a descriptive-analytical method and a phenomenological approach, this paper scrutinizes canonical theological and Hadith texts while offering a structural critique of "liquid modernity" and the "paradox of connectivity." Research findings indicate that in Islamic ontology, the human being is an inherently relational entity. The paradigm of Uns operates within two interconnected layers: the vertical layer (intimacy with the Divine [al-Haqq] as an emotional anchor) and the horizontal layer (brotherhood, mutual social responsibility [Takaful], and the physicality of rituals). By negating alienating factors—such as suspicion and backbiting—and emphasizing "embodied presence" against the superficiality of cyberspace, Islam fills the human existential void. Consequently, the "Theology of Uns," by offering operational models such as reviving the mosque’s function as a "third place," the ethics of neighborliness, and spiritual psychotherapy, creates a sustainable "ontological security." This security, transcending reductionist solutions, reconstructs collective identity in contemporary urban environments.