It is plain that the bishop was the sole judge of the clergy in criminal cases: that he alone decided their differences, and that to him appertained the cognizance of certain offences against the rights of the Church and the sanctions of religion; but as it was his duty to sit with the sheriff in the court of the county, his ecclesiastical became blended with his secular jurisdiction, and many causes, which in other countries had been reserved to the spiritual judge, were decided in England before a mixed tribunal. This disposition continued in force till the Norman Conquest; when, as the reader must have formerly noticed, the two judicatures were completely separated by the new sovereign; and in every diocese "Courts Christian," that is, of the bishop and his archdeacons, were established after the model and with the authority of similar courts in all other parts of the Western Church. The tribunals, created by this arrangement, were bound in the terms of the original charter to be guided in their proceedings by the "episcopal laws," a system of ecclesiastical jurisprudence, composed of the canons of councils, the decrees of popes, and the maxims of the more ancient fathers. This, like all other codes of law, had in the course of centuries received numerous additions. New cases perpetually occurred; new decisions were given; and new compilations were made and published. The two, which at the time of the Conquest prevailed in the spiritual courts of France, and which were sanctioned by the charter of William in England, were the collection under the name of Isidore, and that of Burchard, Bishop of Worms.