For the days shall come upon thee. He now assumes, as it were, the character of a judge, and addresses Jerusalem with greater severity. In like manner the prophets also, though they shed tears over the destruction of those about whom they ought to feel anxiety, yet they summon up courage to pronounce severe threatenings, because they know that not only are they commanded to watch over the salvation of men, but that they have also been appointed to be the heralds of the judgment of God. Under these terms Jesus declares that Jerusalem will suffer dreadful punishment, because she did not know the time of her visitation; that is, because she despised the Redeemer who had been exhibited to her, and did not embrace his grace. Let the fearful nature of the punishments which she endured now alarm us, that we may not, by our carelessness, extinguish the light of salvation, but may be careful to receive the grace of God, and may even run with rigor to meet it.

Cast a trench about thee - This was literally fulfilled when this city was besieged by Titus. Josephus gives a very particular account of the building of this wall, which he says was effected in three days, though it was not less than thirty-nine furlongs in circumference; and that, when this wall and trench were completed, the Jews were so enclosed on every side that no person could escape out of the city, and no provision could be brought in, so that they were reduced to the most terrible distress by the famine which ensued. The whole account is well worth the reader's attention. See Josephus, War, book v. chap. xxii. sec. 1, 2, 3.

For the days shall come upon thee,.... Suddenly, and very quickly, as they did within forty years after this:
that thine enemies; the Romans, and such the Jews took them to be, and might easily understand who our Lord meant:
shall cast a trench about thee, and compass thee round, and keep thee in on every side: which was not only verified in the Roman armies closely besieging them; but particularly in this, as Josephus relates (t) that Titus built a wall about the city, of thirty nine furlongs long, and thirteen forts in it which reached ten furlongs, and all done in three days time; by which means they were pent up, starved, and famished, and reduced to inexpressible distress.
(t) De Bello Jude. l. 6. c. 8.

a trench--a rampart; first of wood, and when this was burnt, a built wall, four miles in circuit, built in three days--so determined were they. This "cut off all hope of escape," and consigned the city to unparalleled horrors. (See JOSEPHUS, Wars of the Jews, 6.2; 12.3,4.) All here predicted was with dreadful literally fulfilled.

Thine enemies shall cast a trench about thee, and compass thee around - All this was exactly performed by Titus, the Roman general.