Of all the branches of the Christian Church the Eastern Orthodox Church with its complicated ritual and its strangely garbed priests, is the most weird and foreign to English-speaking Christians. In this popular book Dr. Zernov endeavours to introduce the outlook and teaching of Orthodoxy to the West. This subject has a special significance at the present time, since the Russian and other Orthodox Churches Joined the World Council of Church in December 1961 and aim at closer co-operation with the Christian West.