In that day shall his strong cities be as a forsaken bough, and an uppermost branch, which {l} they left because of the children of Israel: and there shall be desolation.

(l) As the Canaanites left their cities when God placed the Israelites there, so the cities of Israel will not be able to defend their inhabitants any more than bushes, when God will send the enemy to plague them.

Wesley's Notes

17:9 In - The day of Jacob's trouble, of which he spake ver.4. Uppermost branch - Which he that prunes the tree neglects, because he esteems it useless and inconsiderable. Left - Which they (the Canaanites) left or forsook because of (or for fear of) the children of Israel. And this was a fit example, to awaken the Israelites to a serious belief of this threatening, because God had inflicted the same judgment upon the Canaanites, for the same sins of which they were guilty.

Jamieson-Fausset-Brown Bible Commentary

9. forsaken bough-rather "the leavings of woods," what the axeman leaves when he cuts down the grove (compare Isa 17:6).

which they left because of-rather, "which (the enemies) shall leave for the children of Israel"; literally, "shall leave (in departing) from before the face of the children of Israel" [Maurer]. But a few cities out of many shall be left to Israel, by the purpose of God, executed by the Assyrian.

Matthew Henry's Concise Commentary

17:1-11 Sin desolates cities. It is strange that great conquerors should take pride in being enemies to mankind; but it is better that flocks should lie down there, than that they should harbour any in open rebellion against God and holiness. The strong holds of Israel, the kingdom of the ten tribes, will be brought to ruin. Those who are partakers in sin, are justly made partakers in ruin. The people had, by sins, made themselves ripe for ruin; and their glory was as quickly cut down and taken away by the enemy, as the corn is out of the field by the husbandman. Mercy is reserved in the midst of judgment, for a remnant. But very few shall be marked to be saved. Only here and there one was left behind. But they shall be a remnant made holy. The few that are saved were awakened to return to God. They shall acknowledge his hand in all events; they shall give him the glory due to his name. To bring us to this, is the design of his providence, as he is our Maker; and the work of his grace, as he is the Holy One of Israel. They shall look off from their idols, the creatures of their own fancy. We have reason to account those afflictions happy, which part between us and our sins. The God of our salvation is the Rock of our strength; and our forgetfulness and unmindfulness of him are at the bottom of all sin. The pleasant plants, and shoots from a foreign soil, are expressions for strange and idolatrous worship, and the vile practices connected therewith. Diligence would be used to promote the growth of these strange slips, but all in vain. See the evil and danger of sin, and its certain consequences.