A 20th century Mennonite theologian, Yoder made a tremendous impact on Christian ethics. His work on pacifism helped to make the stance a mainstream topic in Christian theology and his book The politics of Jesus is considered a must read on ethics.
“If the tradition which claims that war may be justified does not also admit that it could be unjustified, the affirmation is not morally serious. A Christian who prepares the case for a justified war without being equally prepared for the negative case has not soberly weighted the prima facie presumption that any violence is wrong until the case for an exception has been made.”
― John Howard Yoder, When War is Unjust: Being Honest in Just-War Thinking
“Incarnation’ does not originally mean (as it tends to today in some theologies of history, and in some kinds of Anglican today) that God took all of human nature as it was, put his seal of approval on it and thereby ratified nature as revelation. The point is just the opposite; that God broke through the borders of man’s definition of what is human, and gave a new, formative definition in Jesus.”
― John Howard Yoder, The Politics of Jesus: Vicit Agnus Noster