In its endeavors to suppress the judicial duel the Church had to weigh opposing difficulties. It could, as we have seen (p. 156), enjoin its members from taking part in such combats and from adjudging them in their jurisdictions; it could decree that priests became “irregular” if death ensued in duels where they gave the benediction, or perhaps even where they had only brought relics on which the combatants took the oaths. But over the secular courts it had only the power of persuasion, or at most of moral coercion, and among the canon doctors there was considerable discussion as to the extent to which it could pronounce participation in the duel a mortal sin, entailing excommunication and denial of the rites of sepulture. When a man sought the duel, when he demanded it of the judge and provoked his adversary to it, he could be pronounced guilty of homicide if death ensued. It was otherwise where an innocent man was accused of a mortal crime and would be hanged if he refused the duel adjudged to him by court. It was argued that the Church was a harsh mother if she forced her children thus to submit to death and infamy for a scruple of recent origin, raised merely by papal command, though the more rigid casuists insisted even on this. All agreed, however, that in civil cases a man ought rather to undergo the loss of his property than to imperil his soul and disobey the Church.[711] * * * * * Perhaps the most powerful cause at work was the revival of the Roman jurisprudence, which in the thirteenth century commenced to undermine all the institutions of feudalism. Its theory of royal supremacy was most agreeable to sovereigns whose authority over powerful vassals was scarcely more than nominal; its perfection of equity between man and man could not fail to render it enticing to clear-minded jurists, wearied with the complicated and fantastic privileges of ecclesiastical, feudal, and customary law. Thus recommended, its progress was rapid. Monarchs lost no opportunity of inculcating respect for that which served their purpose so well, and the civil lawyers, who were their most useful instruments, speedily rose to be a power in the state. Of course the struggle was long, for feudalism had arisen from the necessities of the age, and a system on which were based all the existing institutions of Europe could only be attacked in detail, and could only be destroyed when the advance of civilization and the general diffusion of enlightenment had finally rendered it obsolete. The French Revolution was the final battle-field, and that terrible upheaval was requisite to obliterate a form of society whose existence had numbered nine hundred years.