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 1.18
[1.18.1]  Now it happened that there was one mannote[Synesius.] who, though of serious bent, had yet through philosophy been brought up in a more rustic mould, and had nothing in common with the ways of the city. This man had received, as all men had, very many kindnesses from Osiris;note[Aurlian.] for himself exemption from public services, and for his country lighter services to that man.note[Osiris/Aurelian.] And while innumerable men were making verses at that moment, writing speeches in praise of Osiris, and rendering favors to him in return for favors, he was quite as generously disposed as they (and the more so in that he was more capable) and composed, wrote and sang to the lyre in the Dorian manner, which alone he thought had room for depth of character and expression. These poems he did not give to the public, but if there was any listener in the audience who could understand virile phrases, anyone unable to endure the tickling of pleasure but of open mind, to that one he would address his words. On the one hand he knew that Osiris was an exceptionally acute critic of writings, whether ephemeral or lasting, and on the other hand he refrained from saying anything about Osiris in his presence, partly because he did not regard words as a fitting and equal return for deeds, and partly because owing to the rusticity in which he had been brought up, he was ashamed to be thought a flatterer.
[1.18.4] Typho fired up and was manifestly stung to the quick, but out of respect for the assembled company, he withheld his hands and was prudent of necessity. It was possible, however, to fathom this state of mind by his face, for this passed through various stages of passion. Thus in a short space of time he turned all the colors of the rainbow. He became forthwith more hateful, and went further to the bad; the good conditions that existed under Osiris had disappeared, and he worked other evils besides, harassing the cities for which Osiris had pleaded, and devising some personal evil against him, so that he might never be able to return home in freedom, and would be forced to dwell bewailing his lot, and seeing in prosperity those by whom he was hated.
[1.18.5] While the stranger was in this plight, a god have him new strength, one clearly visible, and bidding him to endure to the end. ‘For not in a period of years, but only of months,’ he said, ‘is the scepter of Egypt destined to lift up the claws of the wild beasts, and to abase the crests of the sacred birds.’
[1.18.6] A cryptic allegory this; and while the stranger recognized the picture as that engraved on obelisks and sacred enclosures, the god imparted to him the understanding of the hieroglyphics, and gave him a token of the time implied. ‘Whenever,’ he said, ‘those who are now in power shall attempt to introduce innovations in our religious rites, then expect that in a short time the Giants (by which he meant the foreigners) shall be cast out, themselves pursued with furies, and if some discord still remains, and if everything is not effaced at once, and if Typho himself remains still in the royal palace, despair not even then of the gods. Here is another token for you: whenever we shall purify the air encircling the earth by water and fire, that air tainted by the breath of the ungodly, then shall Justice come even upon those who are left, and straightway expect then the better dispensation after the removal of Typho. For portentous things of this sort we disperse, burning them with lightning and shattering them with thunder.’
[1.18.7] Then indeed what had been harsh in the past, seemed to the stranger of good augury, and he was no longer distressed at his enforced stay, for through that alone he was to be an eyewitness of the intervention of the gods. For it was not even in the range of human conjecture that a compact force under arms, and allowed by law in time of peace to carry the sword, should be routed without even an opponent. These things he reasoned about,  how they might be, but they seemed to surpass reason.
[1.18.8] Now, when a short time had elapsed, there was a question of a certain evil stamp of religious observance, and a counterfeit of ritual as in the case of coinage, which an old law banishes from the cities, shutting out the impiety beyond the walls. Typho set himself to introduce this through the instrumentality of the foreigners, for he did not dare to do so in person through fear of the Egyptian populace, and sought to make a gift of a temple in the city, breaking the laws of his ancestors. At this moment the stranger began to think that this was what was meant by that prophecy of the god, and, he reflected, ‘I shall probably behold what is to follow’.