Doctrines History 21 Catholic Church 15 Religious aspects 12 Islam 11 Theology, Doctrinal 10 Christianity 7 Reformed Church 7 Early works to 1800 6 Peace 6 Buddhism 5 Controversial literature 5 Anglican Communion 4 Apologetic works 4 Jehovah's Witnesses 4 Protestant churches 4 Biography 3 Cardinals 3 Catechisms 3 Christian ethics 3 Christian life 3 English 3 History of doctrines 3 Judaism 3 Mysticism 3 Nuclear warfare 3 Philosophy 3 Society of Friends 3 Spiritual life 3 Theology 3