The book of Jeremiah records the following prophecy given by the Lord to the prophet Jeremiah (the "70-year prophecy"):
Assuredly, thus said the Lord of Hosts: Because you would not listen to My words, I am going to send for all the peoples of the north -- declares the Lord -- and for My servant, King Nebuchadrezzar of Babylon, and bring them against this land and its inhabitants, and against all those nations roundabout. I will exterminate them and make them a desolation, an object of hissing -- ruins for all time . . . This whole land shall be a desolate ruin. And those nations shall serve the king of Babylon seventy years. When the seventy years are over, I will punish the king of Babylon and that nation and the land of the Chaldeans for their sins -- declares the Lord -- and I will make it a desolation for all time. (Jer 25:8-9, 11-12, 1985 JPS Tanakh)
For thus said the Lord: When Babylon's seventy years are over, I will take note of you, and I will fulfill to you My promise of favor -- to bring you back to this place. For I am mindful of the plans I have made concerning you -- declares the Lord -- plans for your welfare, not for disaster, to give you a hopeful future. When you call Me, and come and pray to Me, I will give heed to you. You will search for Me and find Me, if only you seek Me wholeheartedly. I will be at hand for you -- declares the Lord -- and I will restore your fortunes. And I will gather you from all the nations and from all the places to which I have banished you -- declares the Lord -- and I will bring you back to the place from which I have exiled you. (Jer 29:10-14, 1985 JPS Tanakh)
As Christopher M. Hays notes:
So, Jeremiah prophesied that Babylon would conquer Judaea and rule the Israelites and their land for seventy years, after which God promised to restore them. But did things turn out as planned? Not exactly. The Old Testament is littered with texts trying to account for the way in which subsequent history did not line up with Jeremiah’s timeline. Initially, the biblical authors needed to explain why the exile began to wind down too early; then, they had to reverse their tactics and explain why restoration from exile was taking too long; and finally some of them just threw up their hands and denied that the prophesied restoration was ever even inaugurated (however abortively or impartially). In short, the Hebrew Bible seems a veritable cacophony of voices trying to explain why things did not turn out as Jeremiah had prophesied. (Christopher M. Hays, “Prophecy: A History of Failure?” in Christopher M. Hays, ed. When the Son of Man Didn’t Come: A Constructive Proposal on the Delay of the Parousia [Minneapolis: Fortress Press, 2016], 23-58, here, p. 26, italics in original)
While Hays’ entire essay should be read, as one example of the reinterpretation of Jeremiah’s original prophecy by Ezra-Nehemiah, he writes:
[The editor of Ezra-Nehemiah has to] explain why the restoration from exile had been so sluggish! Even seventy years after the invasion of Judea, things still hadn’t come together as Jeremiah had prophesied. Jeremiah 29:10-14 (cf. 25:11-12) promised that after the seventy years God would return the Israelites from exile and restore their fortunes. But it is not as if all the Israelites had returned to the Promised Land by the time the Temple had been rebuilt. Only a portion of the Israelite population hobbled back to Judaea under Cyrus’s decree (Ezra 2:1-65). When Ezra’s ministry began around 458 BCE, a solid 130 years into the exile, he was still only leading a modest contingent of Israelite exiles to Jerusalem (see Ezra 8:1-20), and even then, their travel required the gracious permission of King Artaxerxes (Ezra 7:11-28). A dozen years after that, Nehemiah undertook his ministry (Neh. 2:1-10), and he too lamented that the exile was far from over (Neh. 1:1-11). Thus, in about 446 BCE, some 141 years after the destruction of the Jerusalem Temple, Nehemiah was still in Persia; the walls of Jerusalem lay in ruins; and those who had supposedly escaped captivity remained “in great trouble and shame” (Neh. 1:3). To compound matters, Nehemiah the governor of Judah, Nehemiah’s predecessors had been exploiting and oppressing the Israelite residents. To put it mildly, the restoration of Israel after seventy years that Jeremiah promised had proven an overstatement; God’s “plans to prosper them and not to harm them” (Jer. 29:11) were not coming to pass as advertised.
So, the editor of Ezra-Nehemiah had to back-pedal. Although he wanted to read the prophecy of Jeremiah as being fulfilled in more-or-less literal, chronological terms, he was obliged to see 515 BC as the beginning of a fulfillment that remained quite incomplete even seventy additional years later. The editor of the book, summoning a pitiably quixotic optimism, seemed to hope that, with men such as Ezra and Nehemiah at the helm, Israel might steer a course toward complete restoration. (Ibid., 28-29, comment in square brackets added for clarification)
Such is further proof of the contingent nature of biblical promises and prophecies.
For more, see the section entitled “The Bible is both God-centered and Man-centered” in my essay: