The fact that while Knox was conducting himself thus, nobody ventured to put a dirk or a bullet into him--despite the obvious strength of the temptation in many quarters--proves that he was by far the most potent human being in Scotland. Darnley, Moray, Lennox were all assassinated, when their day came, though the feeblest of the three, Darnley, had a powerful clan to take up his feud. We cannot suppose that any moral considerations prevented the many people whom Knox had offended from doing unto him as the Elect did to Riccio. Manifestly, nobody had the courage. No clan was so strong as the warlike brethren who would have avenged the Reformer, and who probably would have been backed by Elizabeth. Again, though he was estranged from Moray, that leader was also, in some degree, estranged from Lethington, who did not allow him to know the details of his intrigues, in France and England, for the Queen's marriage. The marriage question was certain to reunite Moray and Knox. When Knox told Mary that, as "a subject of this realm," he had a right to oppose her marriage with any infidel, he spoke the modern constitutional truth. For Mary to wed a Royal Catholic would certainly have meant peril for Protestantism, war with England, and a tragic end. But what Protestant could she marry? If a Scot, he would not long have escaped the daggers of the Hamiltons; indeed, all the nobles would have borne the fiercest jealousy against such an one as, say, Glencairn, who, we learn, could say anything to Mary without offence. She admired a strong brave man, and Glencairn, though an opponent, was gallant and resolute. England chose only to offer the infamous and treacherous Leicester, whose character was ruined by the mysterious death of his wife (Amy Robsart), and who had offered to sell England and himself to idolatrous Spain. Mary's only faint chance of safety lay in perpetual widowhood, or in marrying Knox, by far the most powerful of her subjects, and the best able to protect her and himself.