Pantænus, who became head of the catechetical school at Alexandria about 180, had been a Stoic. His conversion repeats that of Justin. A man of the highest renown for his Grecian learning, he became equally distinguished as a Christian. He devoted himself to preaching. He was also noted as the first who not only commented by word of mouth on the Sacred Scriptures, but wrote his commentaries against Gnostic commentators of the day. For it is remarkable that, in their zeal to get the Scriptures on their side, the Gnostics had preceded the Christians in the explanation of Scripture, which they treated with the utmost latitude of private judgment. Still more distinguished was Clemens, the pupil as well as the successor of Pantænus. Born about the middle of the second century at Alexandria or Athens, and endowed with great ability, he searched all the systems of Greek philosophy. He was full of learning when grace made him a Christian, and from that time he devoted all his powers to deepen his knowledge of the Christian faith, and to convey that knowledge to others, by drawing out a true Gnosis against the false, a main seat of which was at Alexandria, over the school of which he presided. I have taken the seven great converts, Justin, Tatian, Athenagoras, Theophilus, Tertullian, Pantænus, Clemens, who all became apologists of the Church after their conversion, as specimens of the power which she exercised in the second century of drawing the higher spirits among the heathen into her fold. That power did not diminish but increase in the third century. It exerted itself with great effect through the establishment in the course of the second century of a system of learned instruction in the great catechetical schools. The chief of these was at Alexandria; for where the munificence of the Ptolemies had planted and richly endowed a seat of Greek learning, science, and philosophy, which had been enlarged by Tiberius, so that youth thronged to it from all parts of the Roman Empire, now the Christian Church, which probably from its beginning had there the usual school for instruction of catechumens, by degrees enlarged the instruction given in that school, and introduced learned lectures upon the Christian faith. Before long a complete learned education, all that we mean by an university, was set up. The object was not only to instruct Christian youths, but likewise to attract cultured heathen, especially the young, to prepare them gradually, and gain them to the Christian faith. Explanation of the Sacred Scriptures formed the chief point, but likewise grammar, rhetoric, geometry, and philosophy were studied. The exact point of time when all this took effect cannot be assigned; it is probable that it took time to perfect the system. Athenagoras is the first named president, who was followed from the year 170 to 312 by Pantænus, Clemens, Origen, Heraclas, Dionysius, Pierius, Theognostus, Serapion, Peter the Martyr. Each of these had fellow-workers