Although The Egyptian Tale looks like a retelling of a part of the myth of Isis and Osiris, it is obvious that the two brothers Osiris and Typho represent good and bad government. The story, however, is not just a myth, because the man called Osiris can be identified as Aurelian, praetorian prefect of the Eastern Empire during the reign of Arcadius (r.395-408), and one of Synesius' benefactors. The other people in this ancient roman à clef, however, are less easy to identify, but an attempt is made here.
Synesius, On Providence 1.13
[1.13.1]  As soon as Osirisnote had taken over the rule, Typhonote narrowly escaped death from dashing his wicked head on the ground, and knocking it against columns. For whole days he got himself no food, although a most gluttonous man; he rejected drink, although very fond of wine; although he loved sleep, he continued without sleeping, and he was afflicted with wakefulness, though many attempts were made to conjure it away. And although he purposely closed his eyes that his soul might be free from the stings of memory, yet memory is most contentious to anyone who desires to set it aside, so that the image of his evils was with him even when his eyes were closed, and if sleep ever by chance overtook him, he would fare still more wretchedly in dreams, seeing that hill before his eyes, those votes, all those hands raised for his brother; and even when he would have been glad to arise for hatred of the cruel sight, his ears would hum for long with the din of the cheering throng. Nor could he endure to remain at rest, for his soul was distressed, and if he looked out of his house, a succession of misfortunes met him, showing themselves in the words, behavior, and songs of the multitude. It was always ‘Osiris, how fair to behold, how wise in speech is the young king’, and of his high spirit that it was not boastful, and of his gentleness that it was not abased.
[1.13.2] He would return home then and lock himself in, not knowing what to do with his life; no more did his wife, she, another immense evil, her own tirewoman, greedy of the theater and the market-place,  believing, as she wished, that the eyes of all were turned upon her. On this account, she deemed that her husband’s fall from the royal position was an even greater misfortune for herself, thinking that in the alternative case she would confiscate the freedom of the state on a large scale and waste its resources on luxury.
[1.13.3] Now Typho was already of mature years when he fell a victim to her, like a youth in the initial stages of passion, and the half of his misfortune lay in the shame that he felt before the creature to whom he had expressed his ambition to rule in the highest position, sharing the power with her. And she, in her private life also was a most wonderful being, seeking to shine in the most opposite ways, most feminine of women, on the one hand, in seeking a fresh adornment, in adding to her beauty, and in yielding to her nature; most venturesome, on the other hand, in tampering with men’s affairs and in carrying them out, busying herself about a variety of things and being an innovator besides. With these and other ends in view, she had got ready both women of perverse morals and pimps, all of like dispositions, to keep for the gratification of her own tastes both at home and abroad.
[1.13.4] But as for Osiris, only the fact that his son was seen by men reminded the world that there were women’s apartments in his house, and even his child Horus was seldom visible. For the one virtue of a woman Osiris thought was that neither her person nor her name should pass the door of the courtyard. Accordingly, her rise to the pinnacle of fortune did not avert this chaste wife of his from the even tenor of her way; she was apt to be the more retiring owing to the greatness of her rank. Nor did he himself rejoice as one more happy on account of this elevation, for he knew that even had he not attained it, he would not have been any the less happy, inasmuch as each man, once that he wills to be virtuous, is himself steward to himself of such happiness. Therefore of such as dwell with virtue, whether private individuals or rulers, one may observe men equally gay at heart.
[1.13.5] Every life indeed is material for virtue; just as with the tragic actors whom we see on the stage, whosoever has trained his voice well, will take the parts of Creon and Telephus with equal skill, and in no way will robes of purple be superior to rags, so far as the volume and beauty of his declamation are concerned, or his success in bringing down the house by the sound of his strains. He will portray the handmaiden and her mistress alike with the same power of cadence, and whatever mask he puts on, the manager of the theater demands of him that he use it aright. In a like manner God and Fortune bestow upon us lives, as it were masks in the great drama of the universe, and no better or worse is one life than another; but each man makes such use of it as best he may. The earnest man can everywhere succeed in life, whether he act the pauper or king. As to the mask, it makes no difference. Surely the tragic actor would become ridiculous who shunned one mask and seized upon another.  Even in the rôle of the old woman, if he shines in his art, he is crowned and heralded abroad, while if he disgraces himself in the rôle of a king, he is hooted and hissed, and on occasion is even stoned. For no life is really our own, rather are we clad without with the lives of others, and we, the better and the worse of us when we act and reveal the inner voice, are actors of living drama. These lives, then, we have only to put on and take off, as garments.