Charles Ellicott Commentary Jeremiah 21:14

"And I will punish you according to the fruit of your doings, saith Jehovah; and I will kindle a fire in her forest, and it shall devour all that is round about her." — Jeremiah 21:14 (ASV)

I will kindle a fire in the forest thereof. — The “forest” thus referred to may be either literally the woods, then covering a larger surface than in later times, at Kiriath-jearim (Psalms 132:6; 1 Samuel 7:2); or the wood of the lone wilderness of Ziph (1 Samuel 23:15); or the valley of Rephaim (2 Samuel 5:22); or, figuratively, the royal palace, which, from its cedar columns (1 Kings 7:2; 1 Kings 10:21), was known as the house of the forest of Lebanon. (Compare the comparison of the king’s house to Gilead and the head of Lebanon, in Jeremiah 22:6.)

The desolation caused by an invading army such as that of Nebuchadnezzar, cutting down the choice fir-trees of Lebanon and the forest of Carmel (2 Kings 19:23), showed itself in this destruction of forests in its most conspicuous form, and explains the comparative scarcity of trees in modern Palestine. So Assur-nasirpal narrates, in the history of his conquests, how he had cut down the pine, box, cypress, and other trees of the forest (Records of the Past, iii. p. 74).