Proclus. In Remp. Platonis II
That they hold Ananke to be identical to Themis, it is certified no only by the Greek Theogonies, bit also according to the Persian initiation rites of Mithra, in which all invocations of Themis, at the beginning, the middle, and end of the initiation, join Themis Ananke, pronouncing specifically "Themis and Ananke" and this in all the prayers.
In Remp. Platonis II
Some say that the author of this entire myth is not Er, but Zoroaster, and it is as if it was by the name of Zoroaster by which they have made the work known: such is the opinion of the epicurean Colotes of whom we mentioned earlier. Myself, in fact, I have come across four books of Zoroaster On Nature, for which the preface is: "Zoroaster son of Armenios, Pamphylian, maintains the following, all that, having died in battle, he has learned from the gods and all he has derived from the remainder of his inquest." In the midst of these works we find him addressing himself to Cyrus, but he does not specify which Cyrus. He nowhere mentions any details with regards to the myth, except Ananke: he says she is the Air. These books are replete with astrological speculations, and, in a certain place, seem to be opposed to the retrograde revolution which is discussed in the Politics [269 E 3]. Therefore we cannot discern clearly, even if it is actually the name of Zoroaster, and not Er, which was written in the manuscripts [of Colotes], if these books were the original source of the myth of Er. Except that, if we take into account these books and the numerous commentator on this myth, we see clearly that these books place the Sun in the middle of the planets, while the author of the myth places it immediately above the Moon. Thus Plato would not have written this myth after these said books. Others maintain that what has been written (in the copies) is surely Er, but insist that he had been the master of Zoroaster - such is the opinion according to Cronius - , linking in some manner the Er of Pamphylian race to Zoroaster: unless perhaps they intend to link him not to the Persian Zoroaster, but the Pamphylian one, the one precisely of which we claim to have seen read books On Nature.
Comentary on the Timaeus
315 D, F.
The barbarians [Mithraists] call this life-giving source the well of life, the hollow receptacle suggesting together with the quality of a well the virtue of the whole life-giving godhead, wherein are contained the springs of all life, angelic, demoniac, psychical and physical.
If the one is spring-like, so also is the other. What then are we to say? The barbarians give to bowls the name of wells, and so they denote individual souls. This bowl therefore is a bowl of living water; for it is the source of souls, wherein souls...
from a paraphrase of the four books of Ptolemy on stellar influences.
They have natures therefore corresponding to the majesty of their native gods. They worship Aphrodite, whom they call Isis, and the son of Kronos also... the Sun they address as Mithras. Most of them also foretell the future.