The visual imagery which survives from the third and fourth century of Christianity is truly stunning. We have here Christ the good shepherd from a third century representation in the Roman catacomb. The sheep and the shepherd here, one of the earliest representations. Also from the third century here, we have, from Rome, one of the earliest Christian inscriptions. Later, from the fourth century catacombs we have Christ healing the bleeding woman from the Synoptic Gospels. From the end of the second century the pagan philosopher Celsus, whom we will encounter later in writing against Origen, referred to the Great Church. The Great Church was a body of Christians that was spread across the world, living mostly in cities but also in rural areas. They were a vast number of conversions in North Africa and Asia Minor. But further beyond, in Armenia, and Mesopotamia, Christians remained a minority in a hostile world. But the languages which they spoke in the period from 200, ranged from Latin, to Greek, to Syriac, and Coptic. And their forms of worship varied enormously. In many areas, these Christians were organized into churches with bishops and presbyters. And as deacons, we find both men and women. The new members of the faith were taught the essentials through catechisms before they were baptized. And by the third century we find Christians who had grown up in the faith alongside those who had converted. The worship of the church in the third century took many forms. Hymns, prayers, reading of sacred texts and its interpretation, but also the Eucharistic meal. The Eucharist meal was increasingly associated with Christ's sacrifice on the cross. It had a sense of mystery. It was of sacred nature, set apart from all other activities. It formed the body of Christ. However, we mustn't imagine that there was a uniform set of interpretations. In the Eucharistic meal, there was a variety of practices in the church. Nevertheless, by the third century, the church was developing through its communities a sense of unity that extended across its geographical reach. There were believers who had many interpretations of the faith, including who was the figure of Jesus Christ. But this sense of growing community, which I spoke of, should not be mistaken for complete unity of the faith. The Great Church of the third century has been described by one historian as a network of local churches stitched together across several cultural areas, by lines of communication and personal relationships. The bishop of Rome was seen as the senior figure in the church, but there was not an established hierarchy that would emerge later. In addition, there was no agreement on the actual canon of the bible. It's important for us to remember that the most significant figures of Christianity and of the church in this period, were the bishops who held considerable authority. But they also could differ with one another on significant issues of doctrine and practice. In the Great Church of the third century there were many local divisions. And even separations, because the line between orthodoxy and heresy was not at all clear. A good example is the person that we shall consider later when we come to the North African church. That was Tertullian of Carthage. The bishops played a crucial role in the developing of their communities. And with linking of these communities with the wider body of the church, these leaders of the second and third century had to build churches. Build churches from the teaching of the apostolic faith, by interpreting the words of scripture. As the church continued to grow, the faith had to adapt to different cultures, different languages and even to the philosophy, as we shall see, of the ancient world. The breadth of the Great Church is truly astonishing. The Roman Empire at this time, stretched from Britain to the Dura-Europos in Mesopotamia. And by the early third century however, it had encountered considerable difficulties and was in decline. Within the empire, Christians sporadically suffered persecution. The first being that in the beginning of the third century. This was the time of Perpetua, whom we shall meet, who died in Carthage in 203. Origen, whom we shall also encounter, lost his father at this time. It was approximately 50 years later that the emperor Decimus would agree that there should be more persecution. But it lasted only a year, until his death. But it brought the end for many prominent Christians who were victims, including Origen himself who was tortured, and died shortly thereafter. Cyprian, the great bishop, of Carthage was executed following the renewal of persecution in 258 under Valerian. Sixtus the second, the bishop of Rome also died at this time. But the most well known period of persecution which we shall encounter was under Diocletian. The end of the century. It was by this point the empire was in serious economic decline. And the political reforms of the emperor, in which authority was divided into four rulers, failed to stop the rot. Persecution was largely in the east, where Christians were expected to sacrifice to the gods and to the emperor. Churches were destroyed, property confiscated, and holy books were to be handed over. Christians themselves were arrested. The severity of persecution was particular in North Africa, and led to a distinctive Christian culture. Let us get a sense of the spread of the Christian churches in the third century. We need to cast our eye further. For throughout much of the third century, for example, Persian Christians were able to live in relative peace. But however, during this period, as the number of Christians grew, they were affected by the continuous war between the Persian empire and Rome. The Christians in Persia spoke Syriac, and that was the language of their liturgy and of their doctrine. And it was the Persian Christians who sent missionaries to both India and China. Our records tell us that Christianity entered into what's now modern Afghanistan around the year 200. And there seems to have been a link between the churches of Syria and India. It is possible that missionaries might have traveled through the trade routes from Mesopotamia to India. One of the most remarkable stories, however, is the conversion of the Kingdom of Armenia in the third century. It was the first conversion of a royal household, and of a king. A whole kingdom had become Christian. The Bible was translated into Armenian. The great age of the church, the Great Church, saw the extraordinary growth of Christianity. But it was at the same time an age of persecution. Christianity, we must remember, was not a legal faith in either the Persian or Roman Empire. But it was in Rome, and within the Empire, that would dramatically change within a few decades.