ANSWER: Christ quotes these words in Matthew 24:15 as the signal to fiee unto the mountains. But in Luke 21:20 the Roman army encamped in sight of Jerusalem is the signal for the disciples to flee. Hence we infer that the abomination and detestable thing that spreads desolation is the Roman army, at the sight of which on the Mount of Olives before they had dug the trench around the city in A. D. 70, the Christians all made their escape to Pella in Gilead, not one being left behind to perish in the massacre or to glut the slave markets of the world.
— Steele's Answers pp. 205.