[9] That the sign of the cross was used in this manner is apparent from the works of Lucian, a heathen satirical writer; and from the Apology of Tertullian we likewise learn that it was introduced by Christians in their private devotions in the second century. In the earliest and purest era of the Church, however, there is no reason to believe that it was introduced in any other manner than as a private signal expressing the willingness of the party to suffer for Christ. The Church of England, in her baptism, appears to give its true use and explanation in the primitive sense. At the period of which I am writing, superstition had not mingled error with the simplicity of Christian worship. CHAPTER XI. “Child of dust, corruption’s son, By pride deceived, by pride undone; Willing captive, yet be free, Take my yoke and learn of me.” BOWDLER. Where the Christian Church was at this period, was a question naturally occurring to the mind of the Gentile then, and the believer now. Rome anciently stood within the broken centre of a volcano,—an inference drawn by modern geologists from a careful survey of its strata. The city, as it extended, was gradually built over the old quarries from whence the volcanic substances, pozzolana and tufo, were obtained for the buildings of the city. These species of stone were very easily worked, and the spot where they were found was called Arenaria.[10] As these labyrinths extended a considerable way underneath the city, they naturally became the refuge of the unfortunate. They had, therefore, been the hiding-place occasionally of runaway slaves in the time of the old republic; but when the persecution of Nero blazed against the Christians, these gloomy cells afforded a secure refuge to the infant Church of Christ. Here thousands of Christians lived, died, and were buried; here were their churches and their sepulchres; for they, “of whom the world was not worthy,” dwelt in caves and dens, forsaking all things, so that they might but win Christ. The existence of these quarries or catacombs were known to the Roman people; but the intricacies of their winding passages had not been explored perhaps for centuries. With many villas and houses the entrances of the Arenaria communicated; for when the inhabitants professed the new faith, they were able to attend the services of the primitive Church without serious danger; these openings also enabled them to escape to their brethren when denounced to the heathen ruler of their people. In some cases these desolate asylums had not remained inviolate, for more than once the faithful pastor had been torn from his flock and hurried to the block, the fire, or the cross, according as his rank or station might be. The Roman citizen was generally beheaded, the slave was always crucified or burned alive.