The monasteries also played an important part in the economic development of the country. At times, and in certain localities, the economic condition of the people seems to have sunk to a low ebb. Bede tells us that "very often forty or fifty men being spent with want, would go together to some precipice or to the seashore and there, hand in hand, perish by the fall or be swallowed up by the waves."[28] From the earliest times industrial activity had been a feature of monastic life. Speaking of St. Basil, his biographer tells us that "by the labour of his monks over wide desert places, hopeless sterility gave place to golden harvests and abundant vintages."[29] Manual labour was a common employment in the English monasteries.[30] The builders of the monasteries also necessarily introduced new arts into the country. Thus Benedict Biscop brought over masons and glaziers from France.[31] Lamps and vessels for the use of the Church were made, and the craft taught to the Northumbrians.[32] All the furniture and vestments "which Benedict could not procure at home he took care to purchase abroad."[33] The knowledge of the art of fishing by means of nets, which apparently was not known in some parts, was introduced by the monks.[34] Though slavery was not condemned by the Church at this time,[35] yet the Church fostered the feeling that slavery was not consonant with the dignity of the human soul, and the monasteries used their influence in opposing this custom. Aidan employed some of the gifts of money he received for the monasteries, for the redemption of slaves.[36] Wilfrid granted liberty to the slaves on the land that had been bestowed to the monastery founded by him.[37] It must be borne in mind that in this country the monasteries originally were not merely communities of men or women who were dedicated to a life of contemplation, but were essentially centres of missionary enterprise. Bede tells us of monks who went into the surrounding country and villages to preach, baptize, and visit the sick.[38] Of Aidan and his company of "shorn monks" and laymen, we learn that they traversed the country trying to convert those who were not yet converts to Christianity, and stirring up those who had previously accepted the faith to alms and good works.[39] Similarly Chad, one of the disciples of Aidan, proceeded to preach the gospel "in towns, in the open country, cottages, villages, and castles."[40] In brief, at the period with which we are now concerned, these monasteries served the purpose of spiritual outposts, from whence messengers went out to extend the message of the Christian faith.