The Assyrians too, in a city called Heliopolis, worship the sum with an elaborate ritual under the name of Jupiter, calling him “Zeus of Heliopolis.” The statue of the god was brought from the Egyptian town also called Heliopolis, when Senemur (who was perhaps the same as Senepos) was king of Egypt. It was taken to Assyria first (by Opias the ambassador of Delebor, king of the Assyrian, and by Egyptian priests the chief of whom was Partemetis), and, after it had been for some time in Assyria, it was later moved to Heliopolis.  Why this was done and how it came about that, after leaving Egypt, the statue has reached the place where it now is and is worshiped with Assyrian rather than with Egyptian rites I have omitted to mention, because the matter has no bearing on our present topic.  However, the identification of this god with Jupiter and with the sun is clear from the form of the ceremonial and from the appearance of the statue.
The statue, a figure of gold in the likeness of a beardless man, presses forward with the right hand raised and holding a whip, after the manner of a charioteer; in the left hand are a thunderbolt and ears of corn; and all these attributes symbolize the conjoined power of Jupiter and the sun.
 The Temple is held in remarkable awe too as the seat of an oracle, such divination pointing to a faculty of Apollo, who is identified with the sun. For the statue of the god of Heliopolis is borne in a litter, as the images of the gods are carried in the procession at the Circensian Games, and the bearers are generally the leading men of the province. These men, with their heads shaved, and purified by a long period of abstinence, go as the spirit of the god moves them and carry the statue not of their own will but whithersoever the god directs them, just as at Antium we see the images of the two goddesses of Fortune move forward to give their oracles.
 The god is also consulted from a distance, by the sending of sealed letters, and he replies, in order, to the matters contained in the question put to him. So it was that the emperor Trajan, too, when he was about to march with his army from the province of Syria into Parthia, was urged by friends of the most steadfast piety, who had reliable experience of the power of the god, to consult him about the issue of the undertaking. With typically Roman prudence the emperor, by a preliminary test of the trustworthiness of the oracle, took steps to thwart the possibility of hidden human trickery, and begun by sending scaled tablets with a request for a written reply.  To the surprise of the priests, who were, of course, unaware of the nature of the emperor’s tablets, the god bade a sheet of papyrus be brought and ordered it to be sealed, without any writing on it, and dispatched. When Trajan received the document he was filled with astonishment, since the tablets which he had sent to the god also had had no writing on them;  and he then wrote and sealed other tablets, to ask whether he would return to Rome after the war was over. The god thereupon bade a centurion’s vine branch be brought from among the dedicated offerings in the Temple, broken in pieces, and the pieces wrapped in a napkin and sent thus to the emperor. When Trajan’s bones were brought back to Rome after his death the meaning of the oracle’s response was clear, for the emperor’s remains resembled the pieces of the vine branch, and the vine branch itself [as a centurion’s staff] indicated the time of the event which would befall [namely, in time of war].
 That the discourse may not wander too far afield, by mentioning all the gods by name, let me tell you what the Assyrian believe about the sovereignty of the sun. To the god whom they revere as highest and greatest of the gods they have given the name of Adad, a name which, being interpreted, means “One One.”  Him, then, they worship as the most powerful god, but they associate with him a goddess called Adargatis, and to these two deities, by whom they understand the sun and the earth, they ascribe full power over all things. And, instead of using a number of names to express the power shared by these deities in all its forms, they indicate the manifold pre-eminence of this twofold godhead by the attributes which each deity bears.  These attributes of themselves tell of the nature of the sun; for the statue of Adad is distinguished by rays which point downward, to show that the might of heaven is in the fays which pour down from the sun to the earth, but the statue of Adargatis is distinguished by rays which point upward, to show that everything that the earth brings forth owes its birth to the power of the rays sent from above.  Under the statue of Adargatis are figures of lions, to indicate that the goddess represents the earth, on the same principal as that by which the Phrygians have represented the Mother of the Gods, that is to say, the earth, in a car drawn by lions.
 Finally, the theologians point out that the sovereignty of the sun answers to the sum of all the powers that be, and this is shown by the short prayer which they use in their ritual, saying:
o Sun, Ruler of all, Spirit of the world, Might of the world, Light of the world.
 And in the following verses Orpheus too bears witness to the all-embracing nature of the sun:
Hear, O Thou who dost, wheeling afar, ever make the turning circle of thy rays to revolve in its heavenly orbits, bright Zeus Dionysus, Father of sea, Father of land, Sun, source of all life, all-gleaming with thy golden light. (Macrobius, tr. Davies 1969)