"When the spiritual life has put down deep roots, there is a natural, organic evolution into deep nonviolence: the attitude and practice of non-harming. Even individuals who come from aggression naturally progress beyond the need to the resort of violence. The realization of the interconnectedness of all beings brings with it a sense of the utter preciousness of all life. Every being in every species is precious and irreplaceable. Man and women on the spiritual journey who have made this realization would rather suffer harm themselves then harm another. They extend this attitude of non-harming to all sentient beings and to the planet itself. A commitment to deep nonviolence is necessary to the emerging global culture, and to inter-spirituality. Nonviolence adjusts our external actions to our inner attitudes, and makes them consistent with compassion and the demands of love. As we grow in spiritual wisdom, we become more sensitive to the rights of others, including other species. Gentleness, calm, patience, and humility are all aspects of non-harming; they are expressions of this wonderful quality often regarded as an attribute of the divine itself."
Brother Wayne Teasdale in "The Mystic Heart: Discovering Spirituality in the World's Religions"