Peace demands the most heroic labor and the most difficult sacrifice. It demands greater heroism than war. It demands greater fidelity to the truth and a much more perfect purity of conscience.

Thomas Merton (1915–1968) was an American Roman Catholic Trappist monk, poet, author, theologian, student of interfaith understanding, and activist for social change. His work dove deep into the ways in which religions are similar, and he envisioned a more peaceful world through helping people understand and appreciate spiritual paths different from their own. He wrote over fifty books and countless essays on social justice, religion, and theology throughout his life, and he strove to weave mysticism into his works while connecting these beliefs to overarching societal ideas and structures.