Whole Palestina. The Greeks called Philistia τὴν παλαιστίνην συρίαν, or "Syria of the Philistines," whence the Latin "Palestina" and our "Palestine." Isaiah addresses the country as "whole Palestine," because, while it was made up of a number of principalities (1 Samuel 6:18), his message concerned it in its entirety.
The rod of him that smote thee is broken. This can scarcely refer to the death of Ahaz, since Ahaz did not smite the Philistines, but was smitten by them (2 Chronicles 28:18). It may, however, refer to the death of Tiglath-Pileser, which took place only a year or two previously.
Out of the serpent's root shall come forth a cockatrice; i.e. a more poisonous serpent (see note on Isaiah 11:8). Shal-maneser can scarcely be meant, since he does not, appear to have attacked the Philistines.
Probably Sargon is intended, who "took Ashdod" (Isaiah 20:1), made Khanun, King of Gaza, prisoner, and reduced Philtstia generally to subjection. And his fruit shall be a fiery flying serpent. The fruit of the cockatrice will be even more terrible and venomous.
He will resemble the "fiery flying serpent" of the wilderness (Numbers 21:6). Sennacherib is, perhaps, this "fruit." He conquered Ascalon and Ekron, and had the kings of Gaze and Ashdod among his tributaries.