The first stage in the development of Church architecture was reached amid the declining glories of Roman civilization, before the fall of the Empire; but the first model of a Christian church was not built until after the imperial persecutions.  The early Christians worshipped God in upper chambers, in catacombs, in retired places, where they would not be molested, where they could hide in safety.  Their assemblies were small, and their meetings unimportant.  They did nothing to attract attention.  The worshippers were mostly simple-minded, unlettered, plebeian people, with now and then a converted philosopher, or centurion, or lady of rank They met for prayer, exhortation, the reading of the Scriptures, the singing of sacred melodies, and mutual support in trying times.  They did not want grand edifices.  The plainer the place in which they assembled the better suited it was to their circumstances and necessities.  They scarcely needed a rostrum, for the age of sermons had not begun; still less the age of litanies and music and pomps.  For such people, in that palmy age of faith and courage, when the seeds of a new religion were planted in danger and watered with tears; when their minds were directed almost entirely to the soul’s welfare and future glory; when they loved one another with true Christian disinterestedness; when they stimulated each other’s enthusiasm by devotion to a common cause (one Lord, one faith, one baptism); when they were too insignificant to take any social rank, too poor to be of any political account, too ignorant to attract the attention of philosophers,—­any place where they would be unmolested and retired was enough.  In process of time, when their numbers had increased, and when and wherever they were tolerated; when money began to flow into the treasuries; and especially when some gifted leader (educated perhaps in famous schools, yet who was fervent and eloquent) desired a wider field for usefulness,—­then church edifices became necessary.

This original church was modelled after the ancient Basilica, or hall of justice or of commerce:  at one end was an elevated tribunal, and back of this what was called the “apsis,”—­a rounded space with arched roof.  The whole was railed off or separated from the auditory, and was reserved for the clergy, who in the fourth century had become a class.  The apsis had no window, was vaulted, and its walls were covered with figures of Christ and of the saints, or of eminent Christians who in later times were canonized by the popes.  Between the apsis and the auditory, called the “nave,” was the altar; for by this time the Church was borrowing names and emblems from the Jews and the old religions.  From the apsis to the extremity of the other end of the building were two rows of pillars supporting an upper wall, broken by circular arches and windows, called now the “clear story.”  In the low walls of the side aisles were also windows.  Both the nave and the aisles supported a framework of roof, lined with a ceiling adorned with painting.