Synesius of Cyrene (c.370-c.413) was a Neo-Platonic philosopher who became bishop of Ptolemais in the Cyrenaica. He left behind a small corpus of texts that offer much information about daily life in Late Antiquity, and about the christianization of the Roman world.
In Letter 139, written in 395 and addressed to Herculian, a former fellow-student in Alexandria, Synesius expresses his longing to see his friend again. Unlike Letter 138, in which it is suggested that Herculian had left Alexandria, this letter gives the impression that it was Synesius who had to leave, unless he speaks about Alexandria as "my city" and thinks that the presence of Herculian is better than that of the students of the school of Hypatia. Herculian also received letters 137, 145, 140, 141, 142, 146, 143, and 144.
Letter 139 is offered here in the translation by A. Fitzgerald.
Letter 139: Longing for a Lost Friend
 To Herculian
If there is such a sting of persuasion in letters, if even without your living sympathy and charm the images of your character cast such a spell over those who read, to converse with you face to face would be irresistible indeed. For my part, as long as I was in your company, you charmed me by the sweet siren of your voice. Nevertheless, I should not be ashamed to tell you the truth that a pleasure still sweeter would be our second meeting, for the perception of a present good cannot compare with that of an absent good, to him who has once made trial. Moreover, the continuity of the enjoyment steals away the sensation of joy, but he who has been separated even a little while from pleasures, retains a proportionately poignant memory of those things which he actually lacks.
 May you come to me, friend who are so dear to me! Let us take up again our discourses on philosophy, and build up something worthy of our beginnings, that from perfect things a perfect beauty may be manifest, not one that is marred. But if we are fated to remain deprived of each other's company, which God forbid, the loss will certainly be mine alone, for where you are, education flourishes, amongst a multitude of men, and there will be with you many like Synesius and many better than he.
 My city is dear to me because it is my city, but it has become, I know not how, insensible to philosophy. It is therefore not without apprehension that I feel myself alone and without help in the absence of one with whom to share my philosophic frenzy. But even if we should admit that there are some such,
How could I forget Odysseus equal unto the Gods!note[Homer, Odyssey 1.65.]
 Leaving your sacred soul, against what other pieces of wood could I rub myself, and bring forth a luminous child of reason? Who will be so able by every contrivance powerfully to call forth a hidden spark which loves to conceal itself, to ignite it, and reveal a brilliant flame? United or separated, may God always be with us! If God is present, there is a path in every pathless place.
 Farewell; philosophize, and raise the divine within you to the first-born divine. For it is a beautiful thing that my whole letter should say from me to your honoured self what Plotinus, the story goes, said to those present as he released his soul from its body.note[A reference to Porphyry, Life of Plotinus 2.]