The king’s sureties were the archbishop of Canterbury, the bishop of Ely, and William the Marshal. The choice of the archbishop as one of them was good policy on John’s part; and Langton’s acceptance of the office implies no wavering or double-dealing on his side. In so far as it was his inspiration that gave a new force to the enterprise of the barons, by raising it from a struggle for their own privileges into a struggle for the liberties of the English nation, he was in truth, as Roger of Wendover says, their “chief ally”;[976] and for the achievement of its end as he himself conceived it, he did indeed “give them his most faithful help to the utmost of his power.” But the help which he gave them was not that of a partisan; Stephen Langton was at once too true a churchman and too great a statesman, and held too lofty a conception of his proper constitutional functions as primate of all England, to identify himself with any party. The right and the duty of the archbishop of Canterbury was to be the partisan of neither king nor people, but the guide and monitor of both, so far as they would accept his guidance and listen to his admonitions, and the mediator between them whenever mediation was needed. He was by virtue of his office the first adviser of the Crown as well as the guardian of the nation’s rights; and it was only by standing firmly at his post by the king’s side in the former capacity that he could be truly efficient in the latter. Langton’s attitude was evidently understood by both parties at the time. From the moment when the northern barons first asked the king to confirm his great-grandfather’s charter, if not before, John must have known that the hand of the primate was with them in the matter. But he was quite as much alive as they were to the value of such a helper; moreover, he seems to have had the somewhat rare gift of being able to recognize in another man qualities which were conspicuously absent from his own character. Much as he hated Langton, he evidently trusted to his honour and loyalty as implicitly as he trusted to that of William the Marshal. He therefore continued to the end the policy which he had pursued ever since the archbishop’s coming to England. He treated Langton with every mark of confidence and respect; he carefully avoided any step which might have forced him into opposition on ecclesiastical grounds; and in his diplomatic dealings with the barons it was Langton whom he employed as his chief commissioner and representative.