The crucial message of Daniel’s prophecy of the 70 weeks is about the coming of the promised Messiah, the king who inherits the throne of David in Jerusalem. Daniel’s prophecy specified the time when Christ would appear, after the first two sections, of seven weeks, and sixty two weeks. The first section was initiated by the decree of Cyrus, that allowed Jews to return from the exile in Babylon, given near the time of Daniel’s prophecy, in the first years of Darius, about 538 BC. Counting from this start date, seven weeks of leap years (with 13 months) spans 133 years; 7 x 62 is 434 years; the first two sections of the prophecy span 567 years, which would be fulfilled in 28 AD, during the ministry of Jesus.
In the quest for solution to the puzzles presented by Daniel’s prophecy of the 70 weeks, many curious devices have been employed. Otto Zöckler quoted the following list of methods that scholars had devised for interpreting the 70 weeks, by Leonhard Bertholdt (1806). They are methods that various commentators on Daniel had “adopted in order to obviate, by means of exact calculation, the discrepancy between the termin. a quo and ad quem, which was either too large or too small.” 
Dispensationalists and others who insist that the 70 weeks can only mean 490 years look for the start date of the prophecy in the century following the time that the prophecy was given, because otherwise, they think, the prophecy terminates far too early, well before the time of Christ. But the decree of Cyrus in about 538 BC, allowing Jews to return to their land to rebuild the city of Jerusalem, and Daniel’s prophecy of the 70 weeks are dated about the same time, “in the first year of Darius the son of Ahasuerus,” [Daniel 9:1] which suggests that the decree of Cyrus is really the proper start date.
The covenant that is confirmed for one week, in Daniel 9:27, is especially significant, since in one week, all of God’s creative work is accomplished. God worked six days, and rested the seventh, which is a pattern for the entire plan of creation. The seventh day represents the promised rest, for which the saints labor to enter. [Hebrews 4:11]
Preterism and dispensationalism insist that the covenant mentioned in Daniel 9:27, that is to be confirmed for one week, is one that is limited to seven literal years. Both theories deny that the prophecy that “he shall confirm the covenant with many for one week” could possibly refer to the covenant that Christ confirms with Christians throughout the church age, referring to the promises of the gospel.
When the writing appeared on the wall at Belshazzar’s feast, the wise men of Babylon failed to explain it. None of their theories were successful. Similarly attempts by dispensationalists to explain the 70 weeks prophecy of Daniel are defective and unconvincing. Typically, their theories invoke major gaps in a time prophecy, which seems absurd. Time has no gaps! They invoke a gap between the end of the 70 years of exile in Babylon and the start of the 70 weeks, and another one between the 69th and the 70th week. A typical dispensationalist interpretation of the 70 weeks is illustrated in the timeline below.
A good understanding of the prophecy of the 70 weeks can greatly strengthen our faith in the gospel, as Daniel’s prophecy is demonstrably accurate, and when understood properly it helps us to understand other difficult topics, such as the significance of the time, times and a half, which in Daniel 12:7 refers to a period that extends to the end of the age, when all of Daniel’s prophecies will be fulfilled.