Can the churches today confess a common faith which the World Council of Churches has set as the first condition for the unity of the Church? This study analyses the so-called Apostolic Faith project, perhaps the most essential research project of the WCC. The decision to initiate the project was taken at the Faith and Order World Conference held in Bangalore in 1978. The final document was published in the year 1991 with the title Confessing the One Faith. However, it is neither a new ecumenical creed nor a so-called convergence document bringing the churches doctrinally closer to each other. Instead, it is a kind of a theological instrument aiding the churches’ effort to recognise apostolic faith, first in their own church and then in other churches also.
The author shows in the book how during the process it was found necessary to give up the original plan of drawing up a convergence document as was done in the preceding project «Baptism, Eucharist and Ministry». The study chronologically follows the eventful and multiphase completion of the document and draws attention to those problems of fundamental theology and methodology inherent in the conceptions of the Church’s doctrine, its nature and language as well as of the relationship with non-Christian religions, culture and the whole surrounding world. In their ecumenical efforts the churches not only need to take into account each other, but also the diverse challenges arising from the surrounding society, culture and science.