Every church deduces its profession through an uninterrupted tradition from Christ and the apostles. And, indeed, every Christian confession, arising from Christ, must have inevitably reached the present generation through a certain tradition. But this does not prove that any one of these traditions, excluding all the others, is indubitably the correct one. Every twig on the tree goes uninterruptedly back to the root; but the fact that every twig comes from the same root does in no way prove that there is but one twig. The same is true of the churches. Every church offers precisely the same proofs of its succession and even of the miracles in favour of its own authenticity; thus there is but one strict and precise definition of what the church is (not as something fantastic, which we should like it to be, but as something which in reality exists), and this is: the church is an assembly of men, who assert that they, and they only, are in the full possession of the truth. It was these assemblies, which later on, with the aid of the support of the temporal power, passed into mighty institutions, that were the chief impediments in the dissemination of the true comprehension of Christ's teaching. Nor could it be otherwise: the chief peculiarity of Christ's teaching, as distinguished from all the former teachings, consisted in this, that the men who accepted it tried more and more to understand and fulfil the teaching, whereas the church doctrine asserted the full and final comprehension and fulfilment of this teaching. However strange it may seem to us people educated in the false doctrine about the church as a Christian institution, and in the contempt for heresy, it was only in what is called heresy that there was true motion, that is, true Christianity, and it ceased to be such when it stopped its motion in these heresies and became itself arrested in the immovable forms of the church. Indeed, what is a heresy? Read all the theological works which treat about heresies, a subject which is the first to present itself for definition, since every theology speaks of the true teaching amidst the surrounding false teachings, that is, heresies, and you will nowhere find anything resembling a definition of heresy. As a specimen of that complete absence of any semblance of a definition of what is understood by the word "heresy" may serve the opinion on this subject expressed by the learned historian of Christianity, E. de Pressensé, in his _Histoire du Dogme_, with the epigraph, "_Ubi Christus, ibi Ecclesia_" (Paris, 1869). This is what he says in his introduction: "_Je sais que l'on nous conteste le droit de califier ainsi_," that is, to call heresies "_les tendances qui furent si vivement combattues par les premiers Pères. La désignation même d'hérésie semble une atteinte portée à la liberté de conscience et de pensée. Nous ne pouvons partager ces scrupules, car ils n'iraient à rien moins qu'à enlever au christianisme tout caractère distinctif._"