In Daniel 7 the prophecy/vision reveals four empires. Babylon, Meda/Persia, Greece, and Rome. The fourth beast has certain characteristics identical to the picture of the dragon that John showed us in Revelation that desired to devour the child....
The dragon...devil...Satan. Revel.12:3 And there appeared another wonder in heaven; and behold a great red dragon, having seven heads and ten horns, and seven crowns upon his heads.
Pagan Rome...Daniel 7:7 After this I saw in the night visions, and behold a fourth beast, dreadful and terrible, and strong exceedingly; and it had great iron teeth: it devoured and brake in pieces, and stamped the residue with the feet of it: and it was diverse from all the beasts that were before it; and it had ten horns.
Composite of all 4 empires...In Revelation 13, the composite beast also is described thus...
1 ¶ And I stood upon the sand of the sea, and saw a beast rise up out of the sea, having seven heads and ten horns, and upon his horns ten crowns, and upon his heads the name of blasphemy.
Receiving its power, authority, and throne (right to rule) from the dragon, and/or his agent, pagan Rome...2 And the beast which I saw was like unto a leopard, and his feet were as the feet of a bear, and his mouth as the mouth of a lion: and the dragon gave him his power, and his seat, and great authority.
The beast with ten horns in Daniel 7 is Pagan Rome. That all 3 powers are related to Rome is without controversy. Herod was Rome's representative when standing before the mother seeking to devour the child at birth. Rome is the connecting agant in all these different contexts, but did pagan Rome truly give the papacy its power, authority, and throne or right to rule?
In 533 A. D. Justinian, the emperor ruling from Constantinople, proclaimed a decree which recognized the Pope's headship over all the churches of east and west. This decree was actually a letter written by Justinian to Pope John. The letter was included in The Code of Justinian which is a collection of Justinian's laws. It must be remembered that this letter had the force of law. In effect, the Code of Justinian was the standard law of all Europe for over one thousand years until it was replaced in the late 1700's by the Code of Napoleon. Part of Justinian's decree reads as follows:
Therefore, we have exerted ourselves to unite all the priests of the East and
subject them to the See of Your Holiness, and hence the questions which have at
present arisen, although they are manifest and free from doubt, and, according to
the doctrine of Your Apostolic See, are constantly firmly observed and preached by
all priests. . . because you are the head of all the Holy Churches, for We shall exert
Ourselves in every way (as has already been stated), to increase the honor and
authority of your See. . .@ (S. P. Scott, The Civil Law, vol. 12, pp. 11-13).
The significance of this decree is that the Roman Emperor was legitimizing the spiritual authority of the Pope. The state was using its clout to proclaim that only the Pope was the authentic spokesman for orthodox Christianity. This decree was given in 533 A. D.
This decree placed in the Code of Justinian legitimised the secular political power of the Catholic church (through its Popes) under Roman law. However, this legal role had been from time to time practiced by the Popes from the time Constantine had removed the capital to Instanbul (Constantinople). In 533AD the Popes could not freely exercise that authority because of the ruling Ostrogoths in Rome under their king ( I think on memory, Odoacer. (Somehow I don't think that's right...the correct name may come to me). The Ostrogoths decided who would be the bishop of Rome...therefore the Popes only ruled by permission. This, despite the letter from Justinian, was a thorn in the side and greatly offensive to the current bishop because the Ostrogoths, though Christian, were "Arian" (whatever that meant at the time), and certainly did not view themselves as being under Papal authority. This was remedied 5 years later after much pleading from Rome, when Justinian sent his general Belisarius and his army to get rid of the Ostrogoth yoke...the decisive battle taking place in 538AD , a second battle a little later in Ravenna, and from then on the Ostrogoths ceased to be a nation. They were the third and final horn of the 3 to be uprooted. (See Daniel 7:8) before that little horn (the Papacy) could make full independent use of its religious and secular authority and sit upon its throne with confidence and security.