Isaiah 22:11

(11) Ye made also a ditch between the two walls.—Better, a pond or pool, to form a reservoir for the supply of the city. This was probably identical with the “pool of Hezekiah,” known also as the Birket-el-Batrak (“pool of the patriarchs”), between two walls, that to the north of Zaon, and that which runs to the north-east round the Acra. During the rainy season this is supplied by the small conduit which runs from the upper pool along the surface of the ground, and then under the wall near the Joppa gate (Robinson, Researches, i., 437-439). The “old pool” was probably the pool of Siloam (John 9:7), or the king’s pool (Nehemiah 2:14).

Ye have not looked unto the maker thereof.—These material defences, the prophet affirms, will avail but little if they forget Him who was the true “builder and maker” of the city, and who alone can secure its safety.