Jeremiah’s 70-Year Prophecy

The key to the Watch Tower's 'Bible chronology' is their interpretation of the prophecy written in Jeremiah 25:11 [1, p. 463], describing a 70-year period where Judah will serve the king of Babylon [2, p. 26]:

Years before the destruction, the Jewish prophet Jeremiah provided an essential clue to the time frame given in the Bible. He warned “all those living in Jerusalem,” saying: “This whole country will become a desolate wasteland, and these nations will serve the king of Babylon seventy years.” (Jeremiah 25:1, 2, 11, New International Version) The prophet later added: “This is what Jehovah has said, ‘In accord with the fulfilling of seventy years at Babylon I shall turn my attention to you people, and I will establish toward you my good word in bringing you back to this place.’” (Jeremiah 29:10)

They believe that the 70 years began in the 7th month of Zedekiah's 11th year / Nebuchadnezzar's 18th year, when the land of Judah became unworked and deserted [2, p. 27]:

Thus, the 70 years were to be a period when the land of Judah and Jerusalem would enjoy “sabbath rests.” This meant that the land would not be cultivated—there would be no sowing of seed or pruning of vineyards. (Leviticus 25:1-5, NIV) Because of the disobedience of God’s people, whose sins may have included a failure to observe all the Sabbath years, the punishment was that their land would remain unworked and deserted for 70 years.—Leviticus 26:27, 32-35, 42, 43.
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A Jewish revolt brought the Babylonians back to Jerusalem. (2 Kings 24:20; 25:8-10) They razed the city, including its sacred temple, and they took many of its inhabitants captive to Babylon. Within two months, “all the people [who had been left behind in the land] from the least to the greatest, together with the army officers, fled to Egypt for fear of the Babylonians.” (2 Kings 25:25, 26, NIV) Only then, in the seventh Jewish month, Tishri (September/October), of that year could it be said that the land, now desolate and unworked, began to enjoy its Sabbath rest.

They believe that the 70 years ended when the Jews had returned to Jerusalem, which they date to the 2nd year of Cyrus II in 537 BC (following the proclamation in the first year) [2, p. 28]:

Ezra reflected on the prophecies of Jeremiah and linked the end of “the seventy years” to the time when “the LORD moved the heart of Cyrus king of Persia to make a proclamation.” (2 Chronicles 36:21, 22, NIV) When were the Jews released? The decree ending their exile was issued in “the first year of Cyrus the king of Persia.” Thus, by the fall of 537 B.C.E., the Jews had returned to Jerusalem to restore true worship.—Ezra 1:1-5; 2:1; 3:1-5.

Then finally by counting back 70 years they arrive at 607 BC for the destruction of Jerusalem [2, p. 28]:

According to Bible chronology, then, the 70 years was a literal period of time that ended in 537 B.C.E. Counting back 70 years, the start date of the period would be 607 B.C.E.

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