The king having thus, by his prudence, got rid of a dangerous and troublesome rival, and soon after by his valour quelled the insurrections of the earls of Shrewsbury and Mortain, whom he forced to fly into Normandy, found himself in full peace at home and abroad, and therefore thought he might venture a contention with the church about the right of investing bishops; upon which subject many other princes at that time had controversy with their clergy: but, after long struggling in vain, were all forced to yield at last to the decree of a synod in Rome, and to the pertinacy of the bishops in the several countries. The form of investing a bishop was, by delivery of a ring and a pastoral staff; which, at Rome, was declared unlawful to be performed by any lay hand whatsoever; but the princes of Christendom pleaded immemorial custom to authorize them: and king Henry, having given the investiture to certain bishops, commanded Anselm to consecrate them. This the archbishop refused with great firmness, pursuant to what he understood to be his duty, and to several immediate commands of the pope. Both sides adhering to their own sentiments, the matter was carried to Rome, where Anselm went in person, by the king's desire; who, at the same time, sent ambassadors thither to assert and defend his cause; but the pope still insisting, Anselm was forbidden to return to England. The king seized on all his revenues, and would not restore him, until, upon other concessions of the pope, Henry was content to yield up his pretensions to the investiture; but, however, kept the right of electing still in his own hands.