Thus it follows that the festival of “the Conception of Mary” and the festival of “the Immaculate Conception” are not the same thing. Originally only a _festum Conceptionis B.M.V._ was celebrated, and only in course of centuries has a _festum Immaculatæ Conceptionis_ been evolved therefrom. This must not be regarded as a mere question of terms which might be employed interchangeably. Passaglia has not sufficiently emphasised this distinction, and consequently his presentation of the facts creates the impression that there was already in the fifth century a festival of the Immaculate Conception of Mary, which is altogether erroneous. The simple statement of the facts will make this clear, and show that in the course of centuries the feast originally celebrated as the Conception of the Blessed Virgin Mary was changed into a feast of the Immaculate Conception. This change came about in proportion as the matter was made clearer by dogmatic discussion, and as the doctrine of Mary’s exemption from original sin gained adherents in the schools. Even when this doctrine had found general acceptance in the West, and had authoritatively received the support both of conciliar decrees and of papal dogmatic decisions, the ancient title of the feast still remained in use for a long time. If we consult the service-books printed before 1854, we find in them indeed on the 8th December the _festum conceptionis_, but the word _immaculata_ is nowhere found in the office for the feast. An orderly representation of the historical facts concerned will show how this was brought about. Evidence shows that the feast of our Lady’s Conception arose in the Eastern Church, and had gained civil recognition in the Byzantine Empire at a time, when in the West, ecclesiastical circles were still debating whether or not its celebration ought to be permitted. In a constitution entitled, “Concerning the days of the year which are whole holidays and half holidays,” the Emperor Manuel Comnenus in 1166 recognised it as a public festival on which servile work was forbidden. Now it is a known fact that the civil authorities are slow to give recognition to ecclesiastical festivals, and accordingly festivals have often been celebrated by the Church for a long period before they received the recognition of the State. So it was in this case. The Calendar of the Church of Constantinople in which the feast of the 9th December is marked as the “festival of the Conception of St Anne, the mother of the Theotocos,” is a century and a half older than this constitution. It bears the name of the Emperor Basil, meaning the second of this name surnamed Porphyriogenitus (976-1025), and, accordingly, it follows that even then the festival had received some lesser degree of recognition from the State.[524]