Isaiah 14:29

Rejoice not thou, whole Palestina, that is, Philistia, because the rod of him that smote thee is broken, the Philistines being of the opinion that the alliance of Syria and the Northern Kingdom, as a consequence of which Ahaz and Judah had become vassals of Assyria, 2 Kings 16:5, had resulted in breaking the power of Judah, which had only just before that been asserted by Uzziah, 2 Chronicles 26:6; for out of the serpent's root shall come forth a cockatrice, that is, an adder, a still more poisonous serpent, and his fruit shall be a fiery flying serpent, the reference probably being to Hezekiah, who promptly smote the Philistines and definitely brought about their destruction, 2 Kings 18:8.