Amos 2:9

Yet destroyed I, whom they have ungratefully forgotten and forsaken, and set up idol's in competition with me; nay, cast off my law and worship, and embraced idolatry, worshipped idols that never could do them good, nor destroy their enemies; this they did after I had destroyed their enemies. The Amorite; the mightiest nation of all the Canaanites, and therefore expressly mentioned as an instance of God's great mercy, and Israel's great ingratitude: by this nation mentioned all the rest of the Canaanitish nations are to be understood. These Amorites dwelt beyond Jordan, between that and Moab, and their land fell by lot unto Reuben, Gad, and the half tribe of Manasseh. Before them, the children of Israel under the conduct of Moses, Deuteronomy 2:24, &c.; Deuteronomy 3:1, at the very sight of whom these mighty men fled, for God had struck them with terror that they might not stand before Israel. Whose height was like the height of the cedars: the Amorites were men of largest size, they were of the race of the giants, Numbers 13:32,33. This is a proverbial speech, and sets out the Amorites, exceeding ordinary men in stature as much as the cedar exceeds ordinary trees in height. Strong as the oaks; another proverbial speech, denoting their great strength above the strength of other men. I destroyed; utterly rooted them out. His fruit from above: trees propagated by fruit are diminished by destroying the fruit which is the seed of them; so God cut off the children of the Amorites, and thereby prevented all succession. His roots from beneath: this refers to the destroying the old standards, that present generation: this last clause refers to the command God gave, Deuteronomy 7:2.