The rest employed an interpreter when they preached before the laity. To ecclesiastics they spoke the common language of the Latin Church. Their leader, Columbanus, was a man of commanding presence and powerful eloquence, and endowed with a determination of character and intensity of purpose which influenced, either favourably or the reverse, every one with whom he came in contact. From the kings he soon obtained permission to settle in their territories and to erect monasteries; and two monastic establishments soon arose within the recesses of the Vosges mountains, which now divide Alsace from France—those of Luxeuil and Fontaines, to which the youth of the country flocked in numbers for instruction, or for training as monks. [Sidenote: Controversy regarding Easter.] They had not been long established there when the Gaulish clergy became aware that in the new monasteries the festival of Easter was occasionally celebrated on a different Sunday from that observed by the Roman Church, there being occasionally an interval of a week between the two, and sometimes even the violent discrepancy of an entire month. This arose from a difference in the mode of calculating the Sunday on which Easter ought to fall, both in regard to the week within which it ought to be celebrated and the cycle of years by which the month was to be determined. By the law of Moses the passover was to be slain on the fourteenth day of the first month of the year, in the evening (Exod. xii. 2, 3, 6), and the children of Israel were further directed to eat unleavened bread seven days:—‘In the first month, on the fourteenth day of the month, at even, ye shall eat unleavened bread, until the one-and-twentieth day of the month’ (__Ib.__ xii. 18). It was further declared that the month in which the fourteenth day or the full moon fell first after the vernal equinox was to be their first month. In applying this rule to the Christian Easter, the Eastern Church, in the main, adopted it literally, and celebrated Easter on the same day as the Jewish Passover, on whatever day of the week it might fall. The Western Church, however, held that, as our Saviour had risen from the dead on the first day of the week after the Passover, the festival of Easter should be celebrated on the Sunday between the fourteenth and the twentieth day of the moon on the first month of the Jewish lunar year. In order to bring the lunar date into connection with the solar year so as to fix the day of the month on which Easter was to be kept, various cycles were framed by the Church; till at length the Easter cycle of nineteen years was introduced at Alexandria by Anatolius, bishop of Laodicea, in 270, by which Easter was celebrated on the Sunday falling on the fourteenth day of the moon, or between that day and the twentieth on a cycle of nineteen years. In the Western Church, however, the time for celebrating Easter was calculated on a cycle of eighty-four years,