According to the Bible, Cyrus the Great, king of the Achaemenid Empire, was the monarch who ended the Babylonian captivity. In the first year of his reign he was prompted by God to decree that the Temple in Jerusalem should be rebuilt and that such Jews as cared to might return to their land for this purpose. Moreover, he showed his interest in the project by sending back with them the sacred vessels which had been taken from the First Temple and a considerable sum of money with which to buy building materials. The existence of the decree has been challenged.
Cyrus the Great is unconditionally praised in the Jewish sources. It is likely that, after the Persian conquest of Babylon, Cyrus had commenced his relationship with the Jewish leaders in exile, and the Book of Isaiah says that he was anointed by God.
The Hebrew Bible states that Cyrus issued the decree of liberation to the Jews. Cyrus's edict for the rebuilding of the Temple in Jerusalem marked a great epoch in the history of the Jewish people. According to Ezra 4:1-6 "the enemies of Judah and Benjamin" asked to help build the temple, and when this was denied hired counselors to frustrate the people of Judah from completing the rebuilding throughout the reign of Cyrus, Xerxes ('Ahasuerus'), and Artaxerxes, until the reign of Darius II. The work recommenced under the exhortations of the prophets, and when the authorities asked the Jews what right they had to build a temple, they referred to the decree of Cyrus. Darius II, who was then reigning, caused a search for this alleged decree to be made, and it was found in the archives at Ecbatana, whereupon Darius reaffirmed the decree and the work proceeded to its triumphant close.
A chronicle drawn up just after the conquest of Babylonia by Cyrus gives the history of the reign of Nabonidus ('Nabuna'id'), the last king of Babylon, and of the fall of the Babylonian empire. In 538 BC, there was a revolt in Southern Babylonia, while the army of Cyrus entered the country from the north. In June the Babylonian army was completely defeated at Opis, and immediately afterwards Sippara opened its gates to the conqueror. Gobryas (Ugbaru), the governor of Media, was then sent to Babylon, which surrendered "without fighting," and the daily services in the temples continued without a break. In October, Cyrus himself arrived, and proclaimed a general amnesty, which was communicated by Gobryas to "all the province of Babylon," of which he had been made governor. Meanwhile, Nabonidus, who had concealed himself, was captured, but treated honourably; and when his wife died, Cambyses II, the son of Cyrus, conducted the funeral. Cyrus now assumed the title of "king of Babylon," claimed to be the descendant of the ancient kings, and made rich offerings to the temples. At the same time he allowed the foreign populations who had been deported to Babylonia to return to their old homes, carrying with them the images of their gods. Among these populations were the Jews, who, as they had no images, took with them the sacred vessels of the temple.
Speculation abounds as to the reasoning for Cyrus' release of the Jews from Babylon. One argument is that Cyrus was a follower of Zoroaster, the monotheistic prophet: Zoroastrianism played a dominant religious role in Persia throughout its history until the Islamic conquest. As such, he would have felt a kindred spirit with the monotheistic Jews. Another possibility is the magnanimous respect he is ascribed to have evinced for the diverse beliefs and customs of the peoples within his extended kingdom. As one example, upon the conquest of Babylon itself, it is recorded that he paid homage at the temple of the Babylonian god Marduk - thereby gaining the support of the Babylonian people and minimizing further bloodshed. While Jewish tradition, as described previously in Ezra 1:1-8, indicates "the Lord inspired King Cyrus of Persia to issue this proclamation", in the Cyrus Cylinder he pays homage to Marduk. This Babylonian document has been interpreted as referring to the return to their homelands of several displaced cultural groups, one of which could have been the Jews:
From [Babylon] to Aur and (from) Susa, Agade, E?nunna, Zamban, Me-Turnu, Der, as far as the region of Gutium, the sacred centers on the other side of the Tigris, whose sanctuaries had been abandoned for a long time, I returned the images of the gods, who had resided there, to their places and I let them dwell in eternal abodes. I gathered all their inhabitants and returned to them their dwellings. In addition, at the command of Marduk, the great lord, I settled in their habitations, in pleasing abodes, the gods of Sumer and Akkad, whom Nabonidus, to the anger of the lord of the gods, had brought into Babylon. (lines 30-33)
However, it has been argued that it must be referring to people associated to the image's cult instead of deportees. Diana Edelman has pointed at the serious chronological difficulties that arise when we accept that the Jews returned during the reign of Cyrus.
The terms used by the author of Deutero-Isaiah are reminiscent of certain passages in the Cyrus Cylinder: Traditionally, these passages in Isaiah were believed to predate the rule of Cyrus by about 100 years, however, most modern scholars date Isaiah 40-55 (often referred to as Deutero-Isaiah), toward the end of the Babylonian exile (c. 536 BC). Whereas Isaiah 1-39 (referred to as Proto-Isaiah) saw the destruction of Israel as imminent, and the restoration in the future, Deutero-Isaiah speaks of the destruction in the past (Isaiah 42:24-25), and the restoration as imminent (Isaiah 42:1-9). Notice, for example, the change in temporal perspective from (Isaiah 39:6-7), where the Babylonian captivity is cast far in the future, to (Isaiah 43:14), where the Israelites are spoken of as already in Babylon. According to scholar R. N. Whybray, the author of Deutero-Isaiah (chapters 40-55) was mistaken for he thought that Cyrus would destroy Babylon but he did not. Cyrus made it more splendid than ever. But he did allow the Jewish exiles to return home, though not in the triumphant manner which Deutero-Isaiah expected.
Who roused from the east him that victory hails at every step? Who presents him with nations, subdues kings to him? His sword makes dust of them and his bow scatters them like straw. He pursues them and advances unhindered, his feet scarcely touching the road. Who is the author of this deed if not he who calls the generations from the beginning? I, the Lord, who am the first and shall be with the last.
Then the alliance between Cyrus and God is made explicit:
Thus says the Lord to his anointed, to Cyrus, whom he has taken by his right hand to subdue nations before him and strip the loins of kings, to force gateways before him that their gates be closed no more: I will go before you levelling the heights. I will shatter the bronze gateways, smash the iron bars. I will give you the hidden treasures, the secret hoards, that you may know that I am the Lord.
Among the classical Jewish sources, besides the Bible, Josephus (1st century AD) mentions that Cyrus freed the Jews from captivity and helped rebuild the temple. He also wrote to the rulers and governors that they should contribute to the rebuilding of the temple and assisted them in rebuilding the temple. A letter from Cyrus to the Jews is described by Josephus:
I have given leave to as many of the Jews that dwell in my country as please to return to their own country, and to rebuild their city, and to build the temple of God at Jerusalem on the same place where it was before. I have also sent my treasurer Mithridates, and Zorobabel, the governor of the Jews, that they may lay the foundations of the temple, and may build it sixty cubits high, and of the same latitude, making three edifices of polished stones, and one of the wood of the country, and the same order extends to the altar whereon they offer sacrifices to God. I require also that the expenses for these things may be given out of my revenues. Moreover, I have also sent the vessels which king Nebuchadnezzar pillaged out of the temple, and have given them to Mithridates the treasurer, and to Zorobabel the governor of the Jews, that they may have them carried to Jerusalem, and may restore them to the temple of God. Now their number is as follows: Fifty chargers of gold, and five hundred of silver; forty Thericlean cups of gold, and five hundred of silver; fifty basons of gold, and five hundred of silver; thirty vessels for pouring [the drink-offerings], and three hundred of silver; thirty vials of gold, and two thousand four hundred of silver; with a thousand other large vessels. (3) I permit them to have the same honor which they were used to have from their forefathers, as also for their small cattle, and for wine and oil, two hundred and five thousand and five hundred drachme; and for wheat flour, twenty thousand and five hundred artabae; and I give order that these expenses shall be given them out of the tributes due from Samaria. The priests shall also offer these sacrifices according to the laws of Moses in Jerusalem; and when they offer them, they shall pray to God for the preservation of the king and of his family, that the kingdom of Persia may continue. But my will is, that those who disobey these injunctions, and make them void, shall be hung upon a cross, and their substance brought into the king's treasury.".
The historical nature of this decree has been challenged. Professor Lester L. Grabbe has argued that there was no decree but that there was a policy that allowed exiles to return to their homelands and rebuild their temples. He also argues that the archaeology suggests that the return was a "trickle" taking place over perhaps decades, resulting in a maximum population of perhaps 30,000.
The alleged decree of Cyrus permitting--even commanding--the Jews to rebuild the temple and permitting them to return cannot be considered authentic.
Initial text from Easton's Bible Dictionary, 1897 and Schaff-Herzog Encyclopaedia of Religion.