Iona was now in the zenith of its glory. The barren rock, about three miles in length, was covered with monastic buildings, and its cemetery was already adorned with the tombs of saints and kings. Five successors of Columbkill slept in peace around their holy Founder, and a sixth, equal in learning and sanctity to any who preceded him, received the remains of King Egfrid from the hands of his conquerors. This was Abbot Adamnan, to whom Ireland and Scotland are equally indebted for his admirable writings, and who might almost dispute with Bede himself, the title of Father of British History. Adamnan regarded the fate of Egfrid, we may be sure, in the light of a judgment on him for his misdeeds, as Bede and British Christians very generally did. He learned, too, that there were in Northumbria several Christian captives, carried off in Beort's expedition and probably sold into slavery. Now every missionary that ever went out from Iona, had taught that to reduce Christians to slavery was wholly inconsistent with a belief in the doctrines of the Gospel. St. Aidan, the Apostle of Northumbria, had refused the late Egfrid's father absolution, on one occasion, until he solemnly promised to restore their freedom to certain captives of this description. In the same spirit Adamnan voluntarily undertook a journey to York, where Aldfrid (a Prince educated in Ireland, and whose "Itinerary" of Ireland we still have) now reigned. The Abbot of Iona succeeded in his humane mission, and crossing over to his native land, he restored sixty of the captives to their homes and kindred. While the liberated exiles rejoiced on the plain of Meath, the tent of the Abbot of Iona was pitched on the rath of Tara—a fact which would seem to indicate that already, in little more than a century since the interdict had fallen on it, the edifices which made so fine a show in the days of Patrick were ruined and uninhabitable. Either at Tara, or some other of the royal residences, Adamnan on this visit procured the passing of a law, (A.D. 684,) forbidding women to accompany an army to battle, or to engage personally in the conflict. The mild maternal genius of Christianity is faithfully exhibited in such a law, which consummates the glory of the worthy successor of Columbkill. It is curious here to observe that it was not until another hundred years had past—not till the beginning of the ninth century—that the clergy were "exempt" from military service. So slow and patient is the process by which Christianity infuses itself into the social life of a converted people!