The World Council of churches started the Ecumenical Decade of climate justice action with the thematic year 2026 focusing on Climate and Biodiversity. This article advances an ecumenical eco-theological critique of climate change and biodiversity loss by framing ecological destruction as sin rooted in Anthropocene greed. Drawing on theological insights, ethical frameworks, and policy orientations emerging from the World Council of Churches' engagement with creation care, sustainability, and climate justice, the study examines how dominant anthropocentric paradigms and growth-driven economic systems generate profound inequalities between human and non-human life. It argues that ecological sin must be understood as a structural and systemic reality, embedded in political, economic, and cultural institutions that normalize exploitation and environmental harm. Such structures disproportionately impact vulnerable human communities while undermining the intrinsic value and moral standing of non-human creation. Engaging ecotheology, justice-oriented ethics, and public theology, the article critiques financial-driven approaches to sustainability that fail to address questions of natural ecosystem values, spirituality, interdepedency, repentance, and limits to human and non-human rights such as greed lines. In dialogue with ecumenical commitments to justice, peace, and the integrity of creation, the article calls for a reimagining of human responsibility within the community of creation. It concludes by proposing an eco-theological vision oriented toward reconciliation that informs ethical action and public policy in order to challenge Anthropocene greed, and affirm an inclusive ethic of equal care and right for all life within the Earth community.