Thy choicest valleys - Hebrew, ‘The choice of thy galleys;’ meaning the most fertile and most valued lands in the vicinity of the city. The rich and fertile vales around Jerusalem would be occupied by the armies of the Assyrian monarch. What occurs in this verse and the following verses to Isaiah 22:14, is a prophetic description of what is presented historically in Isaiah 36, and 2 Chronicles 32. The coincidence is so exact, that it leaves no room to doubt that the invasion here described was that which took place under Sennacherib.
Set themselves in array - Hebrew, ‘Placing shall place themselves;’ that is, they shall be drawn up for battle; they shall besiege the city, and guard it from all ingress or egress. Rabshakeh, sent by Sennacherib to besiege the city, took his station at the upper pool, and was so near the city that he could converse with the people on the walls Isaiah 36:11-13.