By Kenneth L. Gentry Jr
Dispensationalism incorporates a gap or parenthesis between the sixty-ninth and seventieth weeks. This gap spans the entire Church Age from the Triumphal Entry to the rapture.  The dispensational arguments for a gap of undetermined length between the sixty-ninth and seventieth weeks are not convincing. Let us consider a few of their leading arguments in this regard.
First, the peculiar phraseology in Daniel. Daniel places the cutting off of the Messiah “after the 62 ‘sevens,’ not in the 70th ‘seven.’”  This (allegedly) allows for a gap between the sixty-ninth and seventieth-weeks. If the cutting-off did not occur during the sixty-ninth week or during the seventieth week, a gap must exist between them.
In response it is obvious that seventy occurs after sixty-nine, and thus fits the requirements of the prophecy. Consequently, such an argument does not prove that the word “after” requires a gap. Besides, Daniel mentions only seventy weeks and, as LaRondelle has pointed out, Daniel most certainly does not say “after sixty-nine weeks, but not in the seventieth.”  Such an explanation is a gratuitous assumption demanded by dispensational system requirements. Since Daniel has yet to deal with the seventieth week, and since he clearly deals with the preceding sixty-nine weeks (Da 9:25), it is quite natural to assume this cutting off of the Messiah must be sometime within the seven-year period covered by the seventieth week.
Second, a fatal admission. Walvoord writes: “historically the destruction of Jerusalem occurred in AD 70 almost forty years after the death of Christ.”  So, the argument goes, since Daniel prophesies this event as occurring within the seventy weeks, “the continuous fulfillment theory [is] left without any explanation adequate for interposing an event as occurring after the sixty-ninth seven by some thirty-eight years.” 
I explain the relation of the seventy weeks to the destruction of the temple in AD 70 above. The goal of the Seventy Weeks is not the AD 70 destruction of the temple, which Daniel does not mention in Daniel 9:24. That destruction is a later consequence of certain events that will occur within the seventy weeks. The actual act of God’s reserving judgment (v 24) occurs within the seventy weeks; the later removal of that reservation does not. No necessity at all for a gap exists.
Third, the general tendency in prophecy. Walvoord writes: “Nothing should be plainer to one reading the Old Testament than that the foreview therein provided did not describe the period of time between the two advents. This very fact confused even the prophets (cf. 1 Pet. 1:10–12).”  His argument then is: Old Testament prophecy can merge the first and second advents into one scene, though separated by thousands of years. Consequently, we have biblical warrant for understanding the sixty-ninth and seventieth weeks as merged into one scene, although separated by a gap of thousands of years.