2 Samuel 20:15

Works. Hebrew, a bank, or terrace against the city, and it stood in the trench; (Haydock) so that the town ditch was filled up, (Grotius) or terraces were raised, from which archers assailed the besieged. Joab made a ditch to defend his men from foreign assailants; and he had already taken the outward wall, so that the town could not hold out for any length of time. --- The walls. St. Jerome thinks with battering rams: but they were not yet invented. (Calmet) --- They undermined the walls, while some attempted to pull them down with hooks and ropes, chap. xvii. 13. (Haydock)