Bede the Venerable — as excerpted in the Catena Aurea on Luke 21:20-24

“But how, while the city was already compassed with an army, were they to depart out? except that the preceding word “then” is to be referred, not to the actual time of the siege, but the period just before, when first the armed soldiers began to disperse themselves through the parts of Galilee and Samaria.”