The earl of Clare, besides the lustre which he derived from the greatness of his own birth and the extent of his possessions, was allied to all the principal families in the kingdom; his sister, who was a celebrated beauty, had further extended his credit among the nobility and was even supposed to have gained the king's affections; and Becket could not better discover, than by attacking so powerful an interest, his resolution of maintaining with vigor the rights, real or pretended, of his see.
William de Eynsford, a military tenant of the crown, was patron of a living which belonged to a manor that held of the archbishop of Canterbury; but Becket, without regard to William's right, presented, on a new and illegal pretext, one Laurence to that living, who was violently expelled by Eynsford.

The primate, making himself, as was usual in spiritual courts, both judge and party, issued in a summary manner the sentence of excommunication against Eynsford, who complained to the king, that he, who held "in capite" of the crown, should, contrary to the practice established by the Conqueror, and maintained ever since by his successors, be subjected to that terrible sentence without the previous consent of the sovereign.

Henry, who had now broken off all personal intercourse with Becket, sent him, by a messenger, his orders to absolve Eynsford; but received for answer, that it belonged not for the king to inform him whom he should absolve and whom excommunicate; and it was not till after many remonstrances and menaces that Becket, though with the worst grace imaginable, was induced to comply with the royal mandate.
Henry, though he found himself thus grievously mistaken in the character of the person whom he had promoted to the primacy, determined not to desist from his former intention of retrenching clerical usurpations.

He was entirely master of his extensive dominions: the prudence and vigor of his administration, attended with perpetual success, had raised his character above that of any of his predecessors: the papacy seemed to be weakened by a schism which divided all Europe; and he rightly judged that, if the present favorable opportunity were neglected, the crown must, from the prevalent superstition of the people, be in danger of falling into entire subordination under the mitre.
The union of the civil and ecclesiastical power serves extremely, in every civilized government, to the maintenance of peace and order; and prevents those mutual encroachments which, as there can be no ultimate judge between them, are often attended with the most dangerous consequences Whether the supreme magistrate who unites these powers receives the appellation of prince or prelate, is not material.
The superior weight which temporal interests commonly bear in the apprehensions of men above spiritual, renders the civil part of his character most prevalent; and in time prevents those gross impostures and bigoted persecutions which, in all false religions, are the chief foundation of clerical authority.

But during the progress of ecclesiastical usurpations, the state, by the resistance of the civil magistrate, is naturally thrown into convulsions; and it behoves the prince, both for his own interest and for that of the public, to provide in time sufficient barriers against so dangerous and insidious a rival.
This precaution had hitherto been much neglected in England, as well as in other Catholic countries; and affairs at last seemed to have come to a dangerous crisis: a sovereign of the greatest abilities was now on the throne: a prelate of the most inflexible and intrepid character was possessed of the primacy: the contending powers appeared to be armed with their full force and it was natural to expect some extraordinary event to result from their conflict.
Among their other inventions to obtain money, the clergy had inculcated the necessity of penance as an atonement for sin; and having again introduced the practice of paying them large sums as a commutation, or species of atonement for the remission of those penances, the sins of the people, by these means, had become a revenue to the priests; and the king computed, that by this invention alone they levied more money upon his subjects than flowed, by all the funds and taxes, into the royal exchequer.