HILE there are indeed some rather spectacular prophecies in Daniel 9, there are also some very simple principles. The understanding of God's timeline did not come accidentally or incidentally to Daniel. He was going about his spiritual business in a very definite and intentional way when God rewarded him with some answers.
Daniel read the words of Jeremiah the prophet (Jeremiah 25:11-12, 29:10 & Daniel 9:2). In response, Daniel spent much time in prayer, confessing his sins (and the sins of others) and worshipping God (Daniel 9:3-19). After many appropriate words of repentance, Daniel prayed for the restoration of Jerusalem. It is inexplicable that God has chosen to bring His will to pass in answer to the requests of His people, yet this truth is seen throughout Scripture.
Concerning the prophecy itself: seventy sevens is 490. Even though Daniel had understood the 70 years of Jeremiah's prophecies (Daniel 9:2), as he prayed about it, God peeled back the cover and showed him much more about this number of years. In fact, in Daniel 9:25 & 27 God subdivides the 490 years of judgment into 49 years, plus an additional 434 years followed by an eventual seven last years. In these numbers God revealed to Daniel the fact and the timing of the death of Christ (Daniel 9:26) and the oppressive seven-year reign of the antichrist (as yet unfulfilled) during the seventieth seven years of the 490 (Daniel 9:27). Finally, after 490 years of measured justice (with a very long pause for mercy between year 483 and 484), God will bring swift and complete justice upon the whole earth (Matthew 18:21-22).