Immanentizing the eschaton in context

Providing some context for Voegelin: The two figures he discusses are Augustine and Joachim (of Fiore). Augustine distinguished between the "City of God" and the "City of Man." History progresses towards the eschaton only in the City of God, but not in the City of Man. For Joachim however a transcendental eschaton was not enough. Joachim saw history within the temporal realm as moving toward perfection, and as such, immanentized the eschaton:

The Joachitic eschatology is, by its subject matter, a speculation on the meaning of history. In order to define its special character, it must be set off against the Christian philosophy of history that was traditional at the time, that is, against Augustinian speculation. Into the traditional speculation had entered the Jewish-Christian idea of an end of history in the sense of an intelligible state of perfection. History no longer moved in cycles, as it did with Plato and Aristotle, but acquired direction and destination. Beyond Jewish messianism in the strict sense the specifically Christian conception of history had advanced toward the understanidng of the end as a transcendental fulfilment. In his elaboration of this theoretical insight St. Augustine distinguished between a profane sphere of history which culminates in the appearance of Christ and the establishment of the church. He, furthermore, imbedded sacred history in a transcendental history of the civitas Dei which includes the events in the angelic sphere as well as the transcendental eternal sabbath. Only transcendental history, including the earthly pilgrimage of the church, has direction toward its eschatological fulfilment. Profane history, on the other hand has no such direction; it is a waiting for the end; its present mode of being is that of a saeculum sensescens, of an age that grows old.
By the time of Joachim, Western civilization was growing strongly; and an age that began to feel its muscles would not easily bear the Augustinian defeatism with regard to the mundane sphere of existence. The Joachitic speculation was an attempt to endow the immanent course of history with a meaning that was not provided in the Augustinian conception. And for this purpose Joachim used what he had at hand, that is, the meaning of transcendental history. In this first Western attempt at an immanentization of meaning the connection with Christianity was not lost. The new age of Joachim would bring an increase of fulfilment within history, but the increase would not be due to an immanent eruption; it would come through a new transcendental irruption of the spirit. The idea of a radically immanent fulfilment grew rathre slowly, in a long process that roughly may be called "from humanism to enlightenment"; only in the eighteenh century, with the idea of progress, had the increase of meaning in history become a completely intramundane phenomenon, without transcendental irruptions. This second phase of immaentization shall be called "secularization."
From the Joachitic immanentization a theoretical problem arises which occurs neither in classic antiquty nor in orthodox Christianity, that is, the problem of an eidos of history. In Hellenic speculation, to be sure, we also have a problem of essence in politics; the polis has an eidos both for Plato and for Aristotle. But the acualization of thsi essence is governed by the rhythm of growth and decay, and the rhythmical embodiment and disembodiment of essence in political reality is the mystery of existence; it is not an additional eidos. The soteriological truth of Christianity, then, breaks with the rhythm of existence; beyond temporal successes and reverses lies the supernatural destiny of man, the perfection through grace in the beyond. Man and mankind now have fulfilment, but it lies beyond nature. Again there is no eidos of history, becuase the eschatological supernature is not a nature in the philosophical, immanent sense. The problem of an eidos in history, therefore, arises only when Christian transcendental fulfilment becomes immanentized. Such an immanentist hypostasis of the eschaton, however, is a theoretical fallacy. Things are not things, nor do they have essences, by arbitrary declaration. The course of history as a whole is no object of experience; history has no eidos, because the course of history extends into the unknown future. The meaning of history, thus, is an illusion; and this illusionary eidos is created by treating a symbol of faith as if it were a proposition concerning an object of immanent experience.

Now you are probably wondering, "But what does all this have to do with the Gnostics?" To be continued...