There is nothing in these letters to show what rule had been established. All that is laid down is that the Pascha should be kept everywhere on the same day; and it assumed that the Roman and Alexandrian rules as to Easter were identical, and were well known. As a matter of fact, while the Churches of Rome and Alexandria were at one both in keeping Easter on a Sunday, and on a Sunday after the vernal equinox, they were not agreed in their methods of calculating the Sunday upon which Easter would fall. Hence, long after the Council of Nicaea, several instances occur in which a day was taken for the Easter festival at Rome which differed from the day which the Alexandrian experts had calculated to be the correct day. It is worthy of observation that the Emperor in his letter reprobates what he assumes was the Jewish practice of frequently celebrating two Paschas in the same year. What is probably meant is that the Jews at that time (whatever their earlier practice may have been) did not think it necessary to keep the Passover _after_ the vernal equinox. Now the vernal equinox was taken as the beginning of the tropical or solar year; and it might happen from time to time that the full moon of Nisan fell in one year after the vernal equinox, and in the following civil year before the equinox, which would give two passovers in the same solar year. If this interpretation of the words of Constantine’s letter be correct, it would imply that the Christian Pascha should always be celebrated after the equinox, which was certainly already the general practice. But no specific rule with reference to the equinox is laid down in express terms either by the Fathers of the Council or by the Emperor. It will be observed that in the Letter of Constantine he states that the Lord has left us ‘only one festal day of our deliverance, that is to say, of his holy passion.’ The dominant thought connected with the word Pascha was still that of the Crucifixion. At a later period writers, for the sake of accuracy, made the distinction between the ‘Pascha of the Crucifixion’ (πάσχα σταυρώσιμον) and the ‘Pascha of the Resurrection’ (πάσχα ἀναστάσιμον); and eventually the thought of the Crucifixion disappears from the connotation of the word, which has given the name for what we call Easter to the French (_pâques_); the Italians (_pasqua_); and the Spaniards (_pascua_)[159].