This paper discusses Dharma Master Cheng Yen's religious teachings of purification and benefiting others through Tzu Chi volunteers' living practices of waste recycling and production, international humanitarian relief, as well as vegetarianism and fasting, in the globalization context of environmental ethics and sustainable development. The paper concludes three themes. Firstly, the peaceful example of ethical sustainability across ethnicities, nationalities, and religions is undertaken through the efficient actions of Tzu Chi international humanitarian relief to sustain the ethics of common good of humankind. Secondly, the caring example of moral sustainability is presented through the hard work of the Tzu Chi volunteers at the recycling stations island-wide, and brought alive through the mass media communication system to sustain environmental awareness. Thirdly, the loving example of spiritual sustainability is supported through the dietary improvements of vegetarianism and fasting as a way of curbing desires in order to sustain humanistic spirituality. Tzu Chi's Environmental Humanities has evolved into ethical, moral, and spiritual sustainability as a means to serve as a reference for the discussion of environmental ethics and sustainable development.