The rhetoric of Roman moralising has often seemed alien to modern readers. This book, in linking together studies of apparently diverse topics, might be seen as appropriating a trope of Roman moralistic discourse, presenting arguments concerning different subjects as parallel so that they may serve to reinforce one another. A better understanding of this and similar literary devices, as they operate in Roman moralising texts, can help us to make sense of some features of those texts which modern readers have found puzzling. Let us begin with an apparently bizarre example of this kind of rhetoric (included in the book of rhetorical exercises put together by the elder Seneca):

Numerous debts, which it is a pleasure to acknowledge, have been incurred in writing both this book and the Ph.D thesis on which it is largely based. Keith Hopkins supervised the inception and completion of the thesis with his customary incisiveness; if this book can lay any claim to clarity or elegance, it is largely due to him. As part of the Cambridge regime of musical supervisors, Mary Beard and John Henderson, in their different but equally stimulating ways, also directed my research for a time. I am grateful, too, to John Crook, Peter Garnsey, Fergus Millar, Paul Millet and Andrew Wallace-Hadrill for their comments and criticisms. Friends from other disciplines, David Feldman, James Laidlaw and Paul Taylor, in particular, have also been generous with their time and helped me to negotiate a number of theoretical problems. My sister Elisabeth kindly read and commented on a draft as well.

Over the last two years, my colleagues in the Department of Classics and Archaeology at the University of Bristol have provided me with a challenging and supportive environment in which to think and write. Particular thanks go to Denis Feeney, Duncan Kennedy, Charles Martindale and Thomas Wiedemann, who read and commented on draft versions of the book. I cannot claim to have succeeded in answering all the criticisms offered but know I have learnt a great deal from the attempt.

Throughout Augustine's long life (354–430) friendship was to play an important part, both in his everyday relations with others and in his thought. He valued his close friends highly and many of them remained his friends from youth to old age, men such as Alypius and Severus who, like Augustine himself, became bishops in North Africa. Other friendships developed in later life, as in the case of the government official Marcellinus whom Augustine became acquainted with at the time of the council of Carthage in 411 and with whom he maintained a correspondence when they were separated until Marcellinus' execution in 413. Augustine could also maintain affectionate relations over a number of years with men whom he had never met, as with Paulinus at Nola, with whom a friendship developed through their correspondence because they could recognise the friendly feelings each had for the other and they both adhered to the same Christian ideals. Although Augustine's thought was not static and he was led by a variety of factors to adapt his early ideas on many subjects in the course of his life, it is nevertheless accurate to say that he remained true to the ideal of friendship, in one way or another constantly giving it a central place in his way of life and in his theology, relating it closely to his idea of the supreme good (summum bonum) in terms of which his theological ideas were frequently expressed.

It was during the fourth century, as the threat of religious persecution came to an end and the supreme self-sacrifice, martyrdom, ceased to be a reality of everyday life, that Christian monasticism developed into an organised movement in both the eastern and western parts of the Roman Empire. This century, when monasticism in its various forms was spreading so rapidly, is of great importance for it was at this time that so many of the theories upon which later monasticism was to be based were first worked out. Furthermore, in these early stages of its development the monastic life was still regarded as the life of the true Christian, the Christian who was most intent on the pursuit of perfection, and was not yet seen as something very separate from the life of those Christians who did not completely renounce the things of this world: those who opted for the monastic life were merely regarded, on the whole, as preferring a more radical approach to the question of Christian perfection. As a result of this proximity between the way of the monk and the life of clergy and laity, it is possible to see how the language of the legislators and theorists of monasticism overlaps at many points with the language used by Christian writers of this period in their discussions of friendship: in several aspects the ideals of friendship in Christian terms and the ideals of monasticism appear to coincide.

The theme of this book is friendship, an area of ethics which is not of central concern nowadays, especially when regarded as a relationship of affection between members of the same sex. And although it may in some form still have a part in our everyday lives, possibly offering a pleasant means of passing our spare time, we do not tend to regard it as something to which definite rules of conduct apply. Family relations have taken centre stage in our society and friendship has consequently moved into the wings. The modern view of friendship has little in common with that held in antiquity, even if occasionally, in literary writings, we may find sentiments expressed about friendship which seem to conform to generally accepted ideas on the subject, handed on through the ages and discovered anew to be accurate by each generation of articulate people, as when Charlotte Brontë writes in a letter of I March 1847, ‘To keep friendship in proper order, the balance of good offices must be preserved, otherwise a disquieting and anxious feeling creeps in, and destroys mutual comfort.’ But in general it is not a topic about which we theorise or which is regarded as demanding or problematic.

It may then seem surprising that it should have been such a popular topic and so highly valued in Greece and Rome and even more surprising that it should have been regarded as important within Christianity.

Synesius was born some thirty-five years later than Basil and Gregory, contemporary rather with Augustine in the West and John Chrysostom in the East; in fact, his birthplace in what is now Libya lies roughly equidistant between those of Augustine in North Africa and Chrysosotom at Antioch, all of them in areas which were strongly Christian by the end of the fourth century. It is possible that Synesius was born into a Christian family but one which also appears to have claimed descent from Heracles and apparently originated from Sparta; Synesius grew up with strong ties to his Greek past and to Greek culture generally. He did not study at Athens, however, but at Alexandria, a more cosmopolitan city than Athens with powerful Jewish and Christian traditions alongside the pagan. Here he continued his Classical education under the guidance of Hypatia, the teacher of mathematics and Neoplatonist philosophy, and increased his familiarity with the Neoplatonic philosophy according to the theories and principles of which he was to lead the rest of his life. For even though Synesius' familiarity with Christianity also grew, especially during his time at Constantinople, even though he married a Christian and was prevailed upon to become bishop of Ptolemais in the last years of his life, he never relinquished a Neoplatonic world-view and seems to have accepted Christianity only in so far as he could make it accord with Neoplatonism and interpret it in Neoplatonic terms.

With Augustine we reach the culmination of fourth-century Christian theories of friendship, for it is he who arguably provides the most profound views, touching on many areas of Christian life and doctrine and according a crucial role to friendship in each Christian's progress towards salvation. And yet Augustine, as much as any of the late antique personalities discussed in this book, accepted the legitimacy of many of the theories developed by philosophers and other observers of human nature in Greek and Roman antiquity. Was this because the Classical formulations on the subject of philia/amicitia were merely elegantly expressed clichés, common and acceptable to most cultures? No, although often expressed in memorable and oft repeated form, the ideas on friendship developed in Greece and Rome stand out in the history of ideas because of their sophistication and because of the importance attached to them, as is clear from a wide variety of literary genres. But even these facts would not explain why friendship suddenly became once again a crucial concept among so many of the Christian writers in the fourth century, for Christians were under no obligation to accept everything from their pagan heritage and in fact would only accept such ideas after close scrutiny. Why did these leading Christians decide to adopt or adapt so many of the theories familiar to them from their traditional Classical education, clearly finding them relevant to their own circumstances and even helpful in exploring the implications of their total commitment to Christ?

These extracts from one of Jerome's early letters show that friendship was something of which he had intense experience and which he valued highly in his youth; yet this is a view of him which is easily obscured by his later experiences and writings, offering a portrait of this brilliant but difficult man as one suspicious, sensitive and closed to the charms of friendship, a man for whom the saying ‘Loyalty is rare among men’ became as it were a personal motto. Throughout his life, it would seem, Jerome was able to engage in close relationships only with people who were willing to show him due respect and who would not contradict him. Woe betide anyone who criticised Jerome or refused to fit in with his way of thinking! But as a young man, at home in Stridon (in what is probably now Croatia), while studying at Rome, and then at Trier (one of the new cities of imperial residence) and Aquileia, Jerome was surrounded by a number of close friends who apparently shared his interests and his way of life, men such as Bonosus (the friend referred to in the first quotation above), Heliodorus, Rufinus, Chromatius and the aristocratic Pammachius.

To his contemporaries Paulinus was renowned for his renunciation of his great wealth in favour of a life of poverty and dedication to Christ, as we see from the writings of Ambrose, Augustine and Jerome, while to later generations and the Middle Ages the works of Gregory of Tours and Gregory of the Great made him familiar as a man of great holiness and even as a worker of miracles. But if this man made a dramatic break around the year 390, when he was about thirty-five, rejecting the life of the wealthy landowner in France and Spain and high government official in Italy which he had hitherto led, in order to adopt the ascetic life at Nola in Campania, there was one aspect of his life which continued to be important to Paulinus both before and after his ‘conversion’ to a strictly Christian life and which indeed he regarded as only reaching its fulfilment with his dedication to Christ: this was his unusually strong devotion to friendship. Even in his life of retirement Paulinus managed to maintain a number of his old friendships by means of letters – visits from friends were very rare – and to develop a network of other relationships, mostly among the leading Christians of his day who were pleased to be canvassed for their friendship by someone whom they admired so much but who always treated them with great respect and humility.

Although the focal point of this book is to be the writings concerning friendship of certain prominent Christian writers of the fourth century, their thoughts must be considered against the background of the ideas on the subject formulated and discussed by Greek and Roman writers over a period of more than one thousand years. The outline of this background material must necessarily be brief, concentrating on those theories and expressions concerning friendship which will be referred to and developed later in a Christian context; for more detailed discussions of particular topics the reader must consult those books which provide more elaborate treatments of various aspects of the Classical concept of friendship. But however brief this survey, which aims at pointing out the main developments and continuities in the cultural heritage, must cover not only some of the philosophical theories and the changes in meaning or application of the terms involved (as far as this can be deduced from the available sources), but also the more popular views of the subject as they were handed down, often in the form of proverbs of unknown origin: both these strands are evident in later thought.

To begin with the evidence from Greek literature it must be remembered that in Greek thought the term philia (or philotes in early Greek writings) which is usually translated as friendship, had a far wider extension of meaning and application than our term friendship.

Among Latin writers of the fourth century Ambrose provides an example of a Christian who retained the influence of Classical literary and philosophical forms and ideas in which he had been educated, particularly in his thought about friendship, even after he had made a definite commitment to Christianity. In the case of Ambrose and, as we shall see, Jerome, this is not to impugn their devotion to the Christian faith but rather to indicate a difference between them and, for example, Basil or Augustine who transformed their knowledge of the Classical views on friendship to a far greater degree in using them to work out an orthodox theological framework for their ideas. Although Ambrose, Jerome and even Synesius often placed what they said about friendship in a recognisably Christian context, this transposition only effected a superficial change and their ideas remained dominated by pagan thought on the subject. Together they offer various kinds of evidence for the extent to which the traditional thought on the subject of friendship was still in use at this period.

Ambrose, as the son of the Praetorian Prefect of Gaul, was given a traditional literary and rhetorical education' which led him into a legal career at Rome until he was appointed governor of Aemilia–Liguria, the area of northern Italy of which Milan was the centre. But in 373, only a few years after his appointment to this eminent position, the people of Milan unexpectedly chose this highly educated man, a believing Christian but as yet unbaptised, to be their next bishop.

Another Greek-speaking Christian, whose life (347?–407) spans the decisive period which saw the strengthening of Christianity but the gradual dissolution of the Roman Empire, was John Chrysostom. As bishop of Constantinople for about seven years he lived through a period of great political, social and religious turbulence in the eastern capital during the first years of the fifth century, a time of conflict and change witnessed also by Synesius during the two years he spent there. Of all the events and relationships experienced by Chrysostom in his dramatic life, I have chosen to concentrate on just one friendship in order to gain some idea of his view of the possibility and nature of Christian friendship. This was the friendship, based on a shared and whole-hearted devotion to the service of Christ, which developed at Constantinople between him and a woman, the wealthy and high-born lady Olympias, during the last years of his life and which continued until his death. The source of our knowledge of this relationship is largely restricted to the seventeen surviving letters which Chrysostom wrote to Olympias during his exile and enforced travels through what is now eastern Turkey leading to his death in 407. This inevitably provides a partial view of their relationship, dominated as it was at this time by his loneliness, depression and suffering and sheds an unusual light on a man who is primarily remembered as the brillant preacher in the churches of his native Antioch and then as the powerful bishop of Constantinople, the stern proponent of the ascetic life, the critic of luxury and corruption and the prolific writer, for which he is honoured as a Doctor of the Church.

In the preceding chapters I have given some idea of the Classical and Christian material on the subject of friendship which was available to the writers of the fourth century and which inevitably would have affected their views to some extent. It is now time to consider how these Christians experienced friendship in their own personal lives (as documented primarily by letters between the friends) and to try to see how this experience and their knowledge of earlier theories on the subject influenced their own ideas about the nature of friendship and its role in a life lived strictly according to Christian ideals.

The fact that two of the leading Christian writers and Church men in the Greek East during the fourth century, St Basil the Great who became bishop of Caesarea, and St Gregory of Nazianzus, later patriarch of Constantinople, had a long-lasting and close friendship is well-known, but this fact might lead one to suppose that there was complete agreement between them, whereas actually it is clear that they held rather different views about the way a devoted Christian could best serve Christ and had different expectations about their friendship and where a Christian friend's priorities should lie. In attempting to chart the course of their friendship as it developed at Athens and in Cappadocia over a period of almost thirty years, it is necessary to bear in mind that our knowledge of it is derived almost exclusively from the writings of Gregory, so that Basil's view of it, especially in its early stages, is sometimes unclear, or at least seen only through Gregory's reaction to what Basil says.