Mark 13:5ff. is what is now commonly known as the Olivet Prophecy (it has parallels in Mat. 24 and Luke 21). The majority of the prophecy refers to the destruction that later came on Israel when the Roman army attacked in A.D. 70.1 In Mark 13:14-15 Jesus is saying that, when these terrible things were to happen, the people in Jerusalem should escape from the city, and escape quickly, not even stopping to pick anything up from their houses (it’s similar to the evacuation advice given nowadays in case of fire; e.g.: ‘do not stop to collect personal belongings’2) — stopping could hinder their safety.
The Roman attack and siege was going to be horrific.3 Of course, it would have been even worse for pregnant ladies or for people with little children: not only would they have to get through a terrible tribulation themselves, but they would also have the care and concern for their children, too. Jesus, knowing what was to come, laments this in Mark 13:17.
1. An excellent book on the Olivet Prophecy is John Allfree, The Lord’s Mount Olivet Prophecy 2nd edn (Bible Study Publications, 2006).
2. Advice given by Kent Fire and Rescue Service, here (accessed 23/02/11).
3. The extent of how horrible the siege was can be seen in reports like the one Josephus, a first-century Jewish historian, makes. In War of the Jews, 6.3.4, for example, Josephus retells how a lady under siege in Jerusalem was driven, because of the extremity of the situation, to eat her own child!