Charles Ellicott Commentary Daniel 9:2

"in the first year of his reign I, Daniel, understood by the books the number of the years whereof the word of Jehovah came to Jeremiah the prophet, for the accomplishing of the desolations of Jerusalem, even seventy years." — Daniel 9:2 (ASV)

Understood. He gave special attention to Jeremiah’s prophecy of the seventy years of the Captivity. Two passages occur in that prophet’s writings where the duration of the Captivity is mentioned (Jeremiah 25:11; Jeremiah 29:10), to the former of which Daniel refers (Daniel 9:11–12). It will be observed that there existed at this time a collection of sacred books, consisting of what had been already admitted into the Canon.

Seventy years. It appears from Haggai 1:2 and Zechariah 1:12 that considerable uncertainty prevailed as to the time from which the seventy years were to be reckoned. It has been pointed out (Professor Leathes’ Old Testament Prophecy, p. 179) that three periods of seventy years occur in connection with the Captivity:

1. From B.C. 606, the date of Jeremiah’s prophecy, to B.C. 536, the edict of Cyrus.
2. From B.C. 598, Jehoiachin’s captivity, to B.C. 528, the period of Ezra 4:6.
3. From B.C. 588, the destruction of the Temple, to B.C. 518, the edict of Darius (Ezra 6:1).

In the first year of Cyrus, seventy years had elapsed since the captivity of Daniel, but to him it was a question of melancholy importance whether his computation had begun at the right date.