In institutions, rites, and ceremonies, as well as in organisation, the Church of the third and fourth centuries was very different from that of the first. A pompous ritualism with suggestions of image worship had been introduced.[161:1] Great emphasis had come to be laid upon the sanctity and power of holy water,[161:2] sacred relics and places, pilgrimages, and the use of the cross.[161:3] The development of new ideas in reference to the merit of external works resulted in asceticism and a celibate priesthood, fanatical martyrdom, indiscriminate almsgiving, and various patent methods for spiritual benefits. At the same time the number of Church festivals had greatly increased and now included Easter, Pentecost, Epiphany, and various saints' days.[161:4] These new ideas and practices naturally gave the priest the lofty position of mediator between God and man. A differentiation in the ministry gradually crept in as an outcome of the hierarchical spirit. The Bishop of Rome was elevated above all bishops as God's chosen representative on earth. The bishops were exalted above all the presbyters or priests. The priests in turn held a position far superior to the subordinate officials, who had now come to include sub-deacons, readers, acolytes, precentors or cantors, janitors, exorcists,[162:1] and other officials of minor importance.[162:2] These under officers likewise were cut off from the laity by a pronounced gulf.[162:3] To conduct the general affairs of the Church, synods and councils of the clergy came into existence as early as the second century.[162:4] Roman or Greek assemblies may have suggested the form of the synod, though it is more probable that they sprang spontaneously out of the needs of the Church. These meetings at first were irregular and very informal and resulted either in resolutions with no binding force on the dissentient minority, or in a letter. There were four classes of councils: (1.) The synod of a single diocese which probably existed from the beginning. (2.) The provincial council of the bishops of several dioceses. This type began early in the second century. (3.) General councils consisting of the bishops of several provinces. (4.) Universal councils representing the whole Church. When Constantine gave Christianity legal recognition, councils became more common for the purpose of formulating common rules and dogmas, as for instance Arles (314). After the Council of Nicæa in 325 the validity of earlier decisions was recognised and given the force of imperial law. Thus had the councils changed in a few years from local to general, from recommending to sovereign bodies.[163:1]