Environmental activists often hesitate to link ideas on religion and ecology to ideas on environmental justice, because religion is often identified with enviro-skepticism. But acknowledging religious motivations can help shape environmentalism within the religious worldviews that operate in a majority of the global population. This article looks at how one Indian Jesuit botanist—Father K. M. Mathew—embraced the twin dimensions of faith-based justice and eco-centric spirituality of the Jesuits and pioneered research in botany and environmental conservation in 1970s South India. This article illustrates how religious worldviews can further the cause of environmental justice in a secularized world.