John Gill Commentary 2 Chronicles 30:7

"And be not ye like your fathers, and like your brethren, who trespassed against Jehovah, the God of their fathers, so that he gave them up to desolation, as ye see." — 2 Chronicles 30:7 (ASV)

And be not you like your fathers, and like your brethren, which
trespassed against the Lord God of their fathers
By worshipping the calves, and neglecting the service of God in the temple at Jerusalem; the Targum is, "which acted deceitfully with the Word of the Lord their God:" who therefore gave them up to desolation, as you see ;
some part of the land of Israel being already made desolate by the kings of Assyria, which was very visible.