Luther alludes here to the Archbishop Albert of Mayence, who was, besides, Archbishop of Magdeburg and administrator of the bishopric of Halberstadt. In order to be able to defray the expense of the archiepiscopal tax due to Rome, amounting to thirty thousand guilders, he had farmed the sale of the Pope's indulgences, employing the notorious Tetzel as his agent and sharing the profits with the Pope. In 1518 Albert was appointed cardinal. See Ranke, Deutsche Geschichte, etc., vol. i., p. 309, etc.