This paper offers a theological analysis of the Ecumenical Decade of Climate Justice Action (2025-2034) initiated by the World Council of Churches (WCC), interpreting it as a faith-based response to intersecting inequalities intensified by the global climate crisis. Engaging EUARE's focus on religion and inequality, the study examines the Decade's theological foundations, strategic priorities, and inter-religious advocacy for eco-justice. It argues that the WCC's climate justice framework advances an eco-theological critique of structural injustice, exposing how ecological degradation, economic exploitation, and social marginalization are mutually reinforcing and embedded in unequal power relations. Climate crisis thus appears not only as an environmental emergency but as a moral and spiritual disorder. Situated within the WCC's longstanding commitment to justice, peace, and the integrity of creation, the paper analyzes key policy and theological documents to show how climate justice is framed as a moral, spiritual, and socio-political imperative. Particular attention is given to the mobilization of Christian ecotheologies alongside Indigenous spiritualities and other religious traditions to address the disproportionate impacts of climate change on vulnerable communities, biodiversity, and the wider web of life. The paper further highlights inter-religious dialogue and advocacy as a central strategy, emphasizing partnerships with Indigenous traditions, Islam, Buddhism, Hinduism, and other faith communities. These collaborations seek to build ethical consensus, influence public policy, and support grassroots climate action, particularly in the Global South. The Ecumenical Decade of Climate Justice Action is thus presented as a significant development in contemporary religious responses to climate inequality, with broader implications for the study of religion, ethics, and global justice.