From the very moment that the New Testament lay before the Church in the form and in the relatively final arrangement attested by the Muratorian Fragment and Tertullian (i.e. the Roman Church) it developed practically all the consequences and exercised all the influence that as instrumentum divinum it could develop and exercise. Its authority was as fully recognised as if only one and the same New Testament stood beside the Old Testament. All the long-drawn developments, starting with the beginning of the third century, that were necessary for the production of a really uniform Canon (of twenty-seven books) had practically no significance for its prestige, which was already perfect, or for its consequent effects, which were immediate. The thorough investigation of these extraordinary effects is a task that ought to have been carried out by historical science, but it has been hitherto neglected. I shall endeavour in the following pages to do justice to the task.