2 Chronicles 28:21 Commentary - English Annotations on the Holy Bible by Matthew Poole
Distressed him, or, straitened him, by robbing him of his treasures. But he helped him not, but strengthened him not; a most emphatical expression: for though he weakened his present enemy the Syrian, as is related, 2Ki 16:9, yet really, and all things considered, he did not strengthen Ahaz and his kingdom, but rather weaken them; for by the removing the Syrian, who, though a troublesome neighbour, was a kind of bulwark to him, as to many other enemies, he smoothed the way for himself, a far more dangerous and mischievous enemy, as appears by his invasion of Judah in the very next king’s reign.
Consult other comments:
2 Chronicles 28:21 - The Cambridge Bible for Schools and Colleges
2 Chronicles 28:21 - Adam Clarke's Commentary and Critical Notes on the Bible
2 Chronicles 28:21 - Ellicott's Commentary for English Readers (Old and New Testaments)
2 Chronicles 28:21 - John Gill's Exposition of the Entire Bible
2 Chronicles 28:21 - English Annotations on the Holy Bible by Matthew Poole
2 Chronicles 28:21 - John Trapp's Complete Commentary (Old and New Testaments)
English Annotations on the Holy Bible by Matthew Poole

Matthew Poole (1624–1679) wrote English Annotations on the Holy Bible, completing the chapters as far as Isaiah 58 before his death in 1679. The rest of the Annotations were completed by friends and colleagues among his Nonconformist brethren. The first printing of the completed edition was in 1685, 2 volumes folio, followed by editions in 1688, 1696 (with valuable chapter outlines added by the editors, Samuel Clark and Edward Veale), and the 4th and definitive edition in 1700, the basis of all others.