 Along with his friend and colleague, the Protestant philosopher of religion John Hick, Knitter came under criticism from Cardinal Joseph Ratzinger, later known as Pope Benedict XVI.In 1984 he was one of 97 theologians and religious persons who signed A Catholic Statement on Pluralism and Abortion, calling for pluralism and discussion within the Catholic Church regarding the church's position on abortion.Knitter was born on February 25, 1939, in Chicago, Illinois.