In fact, the rule was, on each avoidance of the abbacy, to fill up the situation from founders’ kin, and, failing a qualified person in the direct line, to choose a successor from a collateral branch.’[136] The monastery of Derry is an instance of this. Aedh, son of Ainmire, the king of Ireland who granted the land, and Columba, the saint who founded the monastery, both belonged to the same tribe—that of the Cinel Conaill. The rule is thus stated in the Brehon Laws: ‘When it is a Church of the Tribe of the Land and the Church of the Tribe of the Saint and of the Land at the same time. That is, the tribe of the land succeeds to the church—that is, the tribe of the saint and the tribe of the land are one tribe in this case, and the saint is on his own land,— The saint, the land, the mild monk, The Dalta Church of fine vigour, The Compairche, and the Deoruid De, By them is the abbacy taken (in their order).’[137] When, however, the saint who founded the monastery belonged to a different tribe from that of the chief from whom the grant was obtained and in whose tribe it was founded, the succession to the abbacy was often retained by the family to whom the saint belonged, from the members of which the abbot was in the same manner supplied. The monastery of Drumcliffe is an instance of this. It was founded by Columba in a district which belonged to a stranger tribe, and in the old Irish Life it is said that ‘he gave the authority, and the clergy and the succession to the Cinel Conaill for ever’—that is, to his own tribe. When this was the case, instead of the same tribe forming a lay and ecclesiastical ‘progenies,’ or family, the two families connected with the succession—the tribe of the land and the tribe of the saint—were different, and the following is the rule in the Brehon Laws:—