He had yet to cope with an adversary more formidable than popular opposition; one who would not yield to temporal tyranny the watch-towers and guardian rights of spiritual liberty.

That adversary was Gregory VII.

Already the tremendous threat had issued: "Appear at Rome on a given day to answer the charges against you, or you shall be excommunicated and cast from the body of the Church." But the infatuated monarch, too proud to recede, hurried on by his impetuous arrogance, and by the unprincipled favorites and corrupt prelates who shared his bounty, loaded the Papal legates with scorn and contumely, and drove them from his presence.
He did not even wait for the sentence of excommunication to fall, that now hung by a hair above his head, but began the attack, as if resolved to have the advantage of the first blow.

Couriers were despatched to every part of the empire, with commands to all the prelates and nobles upon whom he could rely, to assemble at Worms, where he promised to meet them without fail.

Twenty-four bishops and a great number of laymen hastened to obey the summons.