The chief purpose of the documents offered in this section is to illustrate the growth of the papal power and the development of the conflicting claims of the empire and the papacy. The organization of the church was a matter of slow growth, and at first the bishop of Rome actually exercised ecclesiastical authority in a decisive way only in his own diocese. But by 1073 the organization of the church was so developed that the supremacy of the pope over the church and ecclesiastical affairs in the west was in a fair way of becoming an accomplished fact. He had secured the sole right to be called pope, universal, and apostolic. The growth of his temporal power is even more clearly marked. At the time of Constantine the bishop of Rome had no temporal authority. But gradually he acquired power over temporal matters and exercised various secular and even imperial prerogatives, until Gregory VII found it easy to formulate and put forth the claim that the pope was master of the emperor and the real ruler of the world even in temporal things. Before 1073 there was occasional friction between the empire and the papacy, but this did not develop into a real and definite struggle for world supremacy until Gregory VII became pope. Selections are here given to illustrate (1) the election of bishops, and especially the early election of the bishop of Rome, nos. 33, 34, 37, 38; (2) the chief means by which the pope acquired recognition of his ecclesiastical headship in the west, that is, his missionary work, nos. 35, 39, 40; (3) the rebellion of the pope against the rule of the Greek emperors, nos. 41, 42; (4) the acquisition of land and of temporal authority by the pope, nos. 36, 43-46, 54; (5) the development of specific conflicting claims of pope and emperor regarding the election and consecration of the pope, the creation and coronation of the emperor, and the exercise of functions which had been regarded as imperial, nos. 47-53, 55-59. 33. Legislation Concerning the Election of Bishops, Fourth to the Ninth Century. Corpus Juris Canonici. Dist. LXIII, c. vi, vii, and i. In the election of the clergy, especially of the bishops, it was some centuries before the theory and the practice of the church entirely agreed. In theory the laity should have nothing to do with the election of the clergy, but in fact, they have, at various times and in different degrees, exercised authority over such matters. Thus, for instance, the people of Rome had a part in the election of their bishop; the emperors at Constantinople, at first in person, later through the exarch at Ravenna, confirmed his election; Karl the Great and his successors named the bishops of Germany; Otto I and Henry III made and unmade bishops of Rome. This state of affairs lasted well into the eleventh century. The church strove more and more to free itself from all outside influence, while the emperors struggled to retain their control of it.