The synoptic accounts introduce the actual ending sign in the Olivet Discourse differently from one another. Matthew gives us a detail that Mark and Luke do not mention. Mark and Luke merely mention enduring to the end to be saved (as does Matthew just before its unique statement), whereas Matthew further states that the Great Commission will be completed, "and then the end will come." A break that can only be inferred in Mark and Luke is thereby clearly delineated in Matthew.
So, let's review the schema of the Olivet Discourse as I've interpreted it.
The Discourse is Jesus' answer to the question, "What will be the sign of your coming and the end of the age?” In the early segments of his answer, Jesus reveals two general signs which lead up to the end:
What occurs during that final period which is the end? Daniel's 70th Week is what is indicated by the reference to Daniel's Abomination. Therefore, what is actually outlined in the Olivet Discourse is a Labor Period followed by a Delivery Period which culminates in the Return of Christ. The Labor Period is long and drawn out, and has been going for almost 2000 years. The Delivery Period has not begun yet (since the Great Commission has not been accomplished yet), but once it does it will last only seven years, and finish with Christ in Jerusalem ruling and reigning here on earth.
So, let's review the schema of the Olivet Discourse as I've interpreted it.
The Discourse is Jesus' answer to the question, "What will be the sign of your coming and the end of the age?” In the early segments of his answer, Jesus reveals two general signs which lead up to the end:
1) Birth pangs of false Christs, wars, famines, earthquakes, persecutions, falling away, false prophets and lawlessness occurring throughout the age. Like birth pangs they will increase in frequency and intensity through the age. My interpretation of the seals of the Revelation being mostly historical fits in quite well with this description--once a seal has been broken, it's effects continue throughout the age; and
2) The Gospel being preached to the entirety of the world. This effort began at the Day of Pentecost and has moved forward throughout the age (note my interpretation of the First Seal). Regardless of whether progress is assessed by every ethnic group being reached or by every habitable place having a witness, the sign that we are not at the end yet is the continuing effort to complete the Great Commission. Once it has been accomplished, the end is here!The break between the signs leading up the end and the end itself is communicated by the phrase: "then [tote, again] the end will come." The end, in this case, is not a hard stop like a period in punctuation, but is more like a period in history. The end is actually a finite span over which the very last things will occur. What the breaks tells us is that final period will not begin until the Gospel has been preached everywhere.
What occurs during that final period which is the end? Daniel's 70th Week is what is indicated by the reference to Daniel's Abomination. Therefore, what is actually outlined in the Olivet Discourse is a Labor Period followed by a Delivery Period which culminates in the Return of Christ. The Labor Period is long and drawn out, and has been going for almost 2000 years. The Delivery Period has not begun yet (since the Great Commission has not been accomplished yet), but once it does it will last only seven years, and finish with Christ in Jerusalem ruling and reigning here on earth.