Prophecy of 70 Years
There are at least two, arguably three 70 year prophecies in the Bible: one of Isaiah and one (or two) predicted by Jeremiah.
70 Years of Isaiah
Isa 23:15, 17, predicts that the city of Tyre would be destroyed and forgotten for 70 years after which, it would return to its previous “promiscuous” way. The history of ancient tyre is not known well enough to know when this was fulfilled. However, Nebuchadnezzar began a 13 year siege of Tyre in about 575 BC which ended in about 562 BC but Tyre resumed its sovereignty soon after Cyrus became sole ruler of Persia (about 537 BC). It was again captured and destroyed by Alexander in 332 BC. In 315 BC the city was again placed under siege by the Macedonian general Antigonus and captured the following year. In 126 BC Tyre gained its independence from the Seleucid Empire but became a Roman province in 64 BC.
It is also possible to interpret this 70 year period as “the span of a king”, an allusion to the kingdom of Babylon. If this is true then the 70 years is symbolic, in round numbers, for the duration of the 68 years of the Babylonian empire, after which, the city of Tyre recovered.
70 Years of Jeremiah
There are two prophecies of Jeremiah which are possibly the same prophecy. Both Jer 25:11, 12 and Jer 29:10 predict that Judah would serve the king of Babylon for 70 years, during which the land would become waste. This was fulfilled beginning in 605 BC when Nebuchadnezzar took about 10,000 people captive in the first Judean campaign. Two more campaigns followed in 597 BC, and the final in 586 BC. In Oct 539 BC Cyrus defeated the Babylonian kingdom. His first regnal year began in Sep 538 BC and he issued the decree recorded in Ezra 1 in 537 BC. It was also during this first regnal year that Daniel 9 is recorded and refers directly to the prophecies of Jeremiah and the 70 years. The decree went into effect when the Jews organised themselves and departed Babylon probably in 536 BC, 70 years (by inclusive reckoning) after the first captivity of Judah.
2 Chron 36:21 also quotes Jeremiah’s 70 years and says that “the land enjoyed its Sabbath rests all the time of its desolation.” This suggest that the 70 years was to make up for previous years when the 7th year of Sabbath rest was not observed making a total of about 490 previous years – about the total time of the Jewish monarchy from David to Zedekiah.
Daniel 9:2 also refers to Jeremiah’s 70 years of captivity. In Dan 9:2, Daniel says that the 70 years would be the duration of the city’s “desolation”, a reference to the fact that Jews had been held captive by Babylon for almost 70 years. The subsequent prophecy in Daniel 9:24-27 is couched in terms that are seven times greater than the 70 years of Jeremiah.
70 Years of Zechariah
Zechariah 1:12 & 7:5 appears to allude to another 70 years during which the temple remained unbuilt. Nebuchadnezzar destroyed the temple in 586 BC, and later, Zerubbabel and Haggai supervised the completion and rededication in 515 BC, about 70 years later.
70 Weeks of Daniel
Daniel 9:24-27 is a complex prophecy that I will not discuss here other than the main time element of 70 weeks consisting 7 weeks plus 62 weeks plus 1 week. In fact, it is a dual prophecy about the coming of Messiah (with time elements) and about the destruction of Jerusalem. The text simply states, "Seventy weeks have been decreed for your people and your holy city … So you are to know and discern that from the issuing of a decree to restore and rebuild Jerusalem until Messiah the Prince there will be seven weeks and sixty-two weeks … "
The book of Ezra contains several decrees issued by Persian rulers that could possibly be the decree referenced by Daniel. However, Ezra 1:1-4 and Ezra 6:6-12 only contain decrees for rebuilding the temple. Ezra 7:12-26 contains the decree that was to enable the Jews to restore and rebuild the Jerusalem and establish their own government. The date is given as the 7th year of Artaxerxes. This can be dated reasonably well by the methods of Sir Isaac Newton ("Observations on the Prophecies of Daniel and the Apocalypse of St John") using the following references:
- Olympiad Dates: These lists from ancient Greece and Rome traced reigning kings via the 4 yearly cycles of “Olympiads”. Several such lists are available from Xenophon, Thucydides, Plutarch and Julius Afrikanus.
- Ptolemy’s Canon: The great Greek astronomer, mathematician, geographer and astrologer, Claudius Ptolemy (100 – 170 AD) created a very famous and accurate list of kings and their reigns beginning with Nabonassar (747 BC, Babylon) up to Aelius Antonius (160 AD, Rome).
- Elephantine Papyrus: The Island of elephantine in Aswan, Egypt, had a significant Jewish settlement and these people have left a huge trove of documents most of which have been double or triple dated with Babylonia, Persian and other kings in both the Babylonian/Persian lunar calendar and the Egyptian Solar calendar.
- Babylonian Cuneiform Tablets: These large group of documents provide lists of kings who ruled in the area from 626 BC to 75 AD.
- General archaeology: Numerous letters, coins, inscriptions and other varied documents all confirm the chronological data above.
- Astronomical records: There are numerous records of calculable astronomical events such as eclipses in the reigns of Nebuchadnezzar and other kings that fix their chronologies.
Thus, Cyrus began his reign in October 539 BC (when Babylon finally fell), and that his first regnal year began in September 538 BC. Artaxerxes ("Longimanus") ascended the Persian throne in about Jan 464 BC, but the first regnal year of his reign began about Sep 464 BC. Therefore, the fifth month in his seventh year would be about July/August 457 BC. Using these same sources, Sir Isaac Newton correctly observed in his “Observations Upon the Prophecies of Daniel” (page 131): “Now the years of this Artaxerxes began about two or three months after the summer solstice, and his seventh year fell in with the third year of the eighteenth Olympiad; and the latter part thereof, wherein Ezra went up to Jerusalem, was in the Julian Period 4257” [= 457BC].
From Daniel's prophecy, 7 weeks (of years) plus 62 weeks (of years) after 457 BC gives 27 AD. The Gospel of Luke records that the beginning of Jesus ministry was marked by His baptism, which, according to Luke 3:1 occurred in the 15th year of the reign of Tiberius Caesar. Since Tiberius ascended the imperial throne on 19 August 14 AD, his “fifteenth year” would be the twelve months beginning 1 Ethanim (September/October) 27 AD by the non-accession reckoning of the Jews making Jesus’ Baptism occurred about October/November, 27 AD; a good agreement with Daniel.
[NOTE: There is further evidence of this date. Luke also records that Jesus was baptised when He was “about 30 years old” (Luke 3:23). While the exact date of Jesus’ birth is unknown, there is a narrow range from which to choose. It was after the Caesar Augustus’ census of 8 BC which took several years to complete. And, it was before Herod’s death in April 4 BC. Since shepherds were in the fields, Jesus must have been born before Nov 5 BC and probably about Aug - Oct 5 BC. In Oct 27 AD, He would have been 31 years old, or “about 30 years old”.]
Lastly, and only very briefly, it is during the last week of the 70 weeks (of years) that Messiah would be "cut off" in the midst of the week. But I will not go into this here. The prophecy also contains material about the "abomination of desolation", namely the destruction of Jerusalem - see below.
Jesus refers to Isa 61:1-3 as the keynote of His ministry in His first sermon (Luke 4:18, 19). Later, Jesus also quotes Daniel in Matt 24:15, 16, Mark 13:14, Luke 21:20-22. Unfortunately, this was fulfilled in 70 AD by General Titus under orders from his father, Emperor Vespasian.