"The burden of Damascus. Behold, Damascus is taken away from being a city, and it shall be a ruinous heap. The cities of Aroer are forsaken: they shall be for flocks, which shall lie down, and none shall make them afraid. The fortress also shall cease from Ephraim, and the kingdom from Damascus, and the remnant of Syria: they shall be as the glory of the children of Israel, saith the LORD of hosts."
The events of this passage likely took place when Tiglathpileser III attacked northern Israel and Syria (II Kings 16:9). If so, this prophecy was placed here not chronologically but topically.
This passage is labeled as the burden of Damascus; however, its content deals more with northern Israel than it does with Syria. This is likely due to the fact that Pekah had allied himself with Rezin against Judah and would therefore feel the sting of God's judgment as both he and his close ally of Syria were attacked and overcome.
Whether or not all of these events came to pass during the conquests of Tiglathpileser or whether they carried over into the reigns of the following Assyrian kings cannot be stated with definite accuracy; however, one thing is for certain, after God's judgment came, the glorious nature of Damascus was gone. Ahaz believed that the false gods of Damascus had overcome him. In light of this, he turned to them in sacrifice (II Chronicles 28:23). God's destruction of Damascus and the deportation of its inhabitants stand as a testimony to the deceptive nature of man's reasoning. Ahaz and his people were not overcome by gods more powerful than the God of Israel, they were overcome by their own rebellion.
Deuteronomy 2:36 places Aroer along the banks of the Arnon River. The name of the city means "ruins." There seems to be somewhat of a play on words as God predicts ruinous heaps for the city and its surrounding villages.
Along with the subjugation of Damascus and Syria, the Lord interjects the fall of Ephraim (northern Israel). The early stages of this subjugation took place when Tiglathpileser made his push westward in 734 BC; however, Ephraim was not completely subjected until 722 BC when Samaria was taken by Sargon.
The comparison of the last verse is amazing when one considers God's promises upon Israel if she would obey Him. God warned Syria that her glory would become as feeble as Israel's. In this sad comparison one finds an underlying principle. The rejection of truth brings weakness, not strength. When Israel should have excelled in glory, she was used as a negative example because of her rebellious choices. Undoubtedly, Israel's alliances seemed rewarding in many ways, but the end result was disastrous. The temporary strength and stability were momentaneous at best.