But the new conscience found most characteristic expression not in its restraints and prohibitions but in its impulsions to altruistic activity and endeavor. In our account of the primitive ethical ideals of Greece and Rome we noticed how the virtue of altruism or self-abnegation for the common good was hidden under the guise of courage.[648] It was therefore no new virtue which Christianity brought into the world when it proclaimed the supreme moral excellence of self-renunciation for others. What it did was to widen the circle of those for whom the supreme sacrifice should be made, and to give the virtue fuller and richer content. It thus imparted fresh impulse to that altruistic movement which we have seen to characterize the last centuries of the civilization of Greco-Roman antiquity. The deepened ethical sentiment found various forms of expression, but the most important of these was the great missionary propaganda which, during the centuries from the sixth to the ninth, carried the new gospel to the pagan German tribes of Europe. Lecky regards this as the chief altruistic movement of the medieval period. This conquest of the continent for Christianity was effected in large part by men whose fervid zeal for social service had been kindled in the quiet and holy atmosphere of the cloister.[649] The movement was inspired and maintained by that same spirit of self-devotion which animated the missionaries of the apostolic age of Christianity. The declaration of the first great apostle to the gentiles, St. Paul, that he would himself willingly be a castaway if thereby he might secure the salvation of others, could have been made by many a self-devoted monk-apostle who won a like crown of martyrdom. In the romance of Christian missions the monastic chronicles of Iona and Lindisfarne and St. Gall, and the tales of the labors and martyrdom of Saints Columba, Wilfrid, Boniface, and a great company of others will never cease to enthrall the imagination so long as the virtue of self-renunciation is esteemed and reverenced among men. This great missionary movement which brought within the pale of the Church the northern peoples is of transcendent interest to the student of the history of morals, not merely because it is such a splendid exhibition of the altruistic spirit of Christianity, but also because the success of these medieval missions meant, besides the winning of the barbarians to a new religion, the winning of them to a new moral life; for to give a people a new religion is to give them also a new conscience. [Sidenote: Almsgiving and the founding of charitable institutions]