And this doctrine of the divine right of the people to raise up and pull down princes, after obtaining the sanctions of religion, was made to stand on broader grounds, and was strong enough to resist both Church and king. In the struggle between the House of Bruce and the House of Plantagenet for the possession of Scotland and Ireland, the English claim was backed by the censures of Rome. But the Irish and the Scots refused it, and the address in which the Scottish Parliament informed the Pope of their resolution shows how firmly the popular doctrine had taken root. Speaking of Robert Bruce, they say: "Divine Providence, the laws and customs of the country, which we will defend till death, and the choice of the people, have made him our king. If he should ever betray his principles, and consent that we should be subjects of the English king, then we shall treat him as an enemy, as the subverter of our rights and his own, and shall elect another in his place. We care not for glory or for wealth, but for that liberty which no true man will give up but with his life." This estimate of royalty was natural among men accustomed to see those whom they most respected in constant strife with their rulers. Gregory VII. had begun the disparagement of civil authorities by saying that they are the work of the devil; and already in his time both parties were driven to acknowledge the sovereignty of the people, and appealed to it as the immediate source of power. Two centuries later this political theory had gained both in definiteness and in force among the Guelphs, who were the Church party, and among the Ghibellines, or Imperialists. Here are the sentiments of the most celebrated of all the Guelphic writers: "A king who is unfaithful to his duty forfeits his claim to obedience. It is not rebellion to depose him, for he is himself a rebel whom the nation has a right to put down. But it is better to abridge his power, that he may be unable to abuse it. For this purpose, the whole nation ought to have a share in governing itself; the Constitution ought to combine a limited and elective monarchy, with an aristocracy of merit, and such an admixture of democracy as shall admit all classes to office, by popular election. No government has a right to levy taxes beyond the limit determined by the people. All political authority is derived from popular suffrage, and all laws must be made by the people or their representatives. There is no security for us as long as we depend on the will of another man." This language, which contains the earliest exposition of the Whig theory of the revolution, is taken from the works of St. Thomas Aquinas, of whom Lord Bacon says that he had the largest heart of the school divines. And it is worth while to observe that he wrote at the very moment when Simon de Montfort summoned the Commons; and that the politics of the Neapolitan friar are centuries in advance of the English statesman's.