The bow was the national weapon of Elam, and therefore the "chief of their might," that on which their strength in war depended.

I will break the bow of Elam - They were eminent archers; and had acquired their power and eminence by their dexterity in the use of the bow. See Isaiah 22:6. Strabo, Livy, and others speak of their eminence in archery.

Thus saith the Lord of hosts, I will break the bow of Elam,.... The inhabitants of this country were famous for their skill in archery; See Gill on Isaiah 22:6; this the Lord threatens to break, so that it, should be useless, and of no more service to them to defend themselves, or annoy others. Their strength, as the Targum; that in which their great strength and security lay; in which they put their trust and confidence, as follows:

the chief of their might; which may be interpreted, by way of apposition, of their bow, the chief instrument of their might and power; or may design their mighty men, the archers themselves, who should be destroyed, even Elam itself, and all the inhabitants of it; especially their warriors, who should be slain or carried captive.

"Thus saith Jahveh of hosts: Behold, I will break the bow of Elam, the chief part of their strength. Jeremiah 49:36. And I will bring upon Elam four winds from the four ends of the heaven, and I will scatter them towards all these winds; and there shall be no nation where the scattered ones of Elam shall not come. Jeremiah 49:37. And I will make Elam terrified before their enemies, and before those who seek their life; and I will bring on them evil, the heat of my wrath, saith Jahveh; and I will send after them the sword, until I consume them. Jeremiah 49:38. And I will place my throne in Elam, and will destroy thence king and princes, saith Jahveh. Jeremiah 49:39. But it shall be in the end of the days, that I will turn the captivity of Elam, saith Jahveh."

Elam's martial power is to be destroyed, and its population scattered to the four winds among all nations (Jeremiah 49:25.). The Lord will make them terrified before their enemies, and let them be pursued by the sword till they are swept away (Jeremiah 49:37). In the country itself He will hold a tribunal, and destroy king and priests out of it (Jeremiah 49:38). In Jeremiah 49:35, the bow, as the chief weapon of the Elamites (cf. Isaiah 22:6), is mentioned, by synecdoche, instead of all offensive and defensive weapons, for all the means of resistance and attack employed by this warlike nation. This, indeed, is shown by the apposition, "the first-fruits (i.e., the chief part) of their strength" or valour. To break the bow in pieces is thus equivalent to rendering defenceless. The plural suffix in גּבוּרתם points to Elam as a nation - the Elamites. Hitzig, Graf, and older expositors make an assumption which is both unnecessary and incapable of proof, that קשׁת stands for גבּורים, and means "the valiant, brave people of war," as in Isaiah 21:17 and 1 Samuel 2:4; but neither in these passages can the alleged meaning be fully made out.

Thus saith the LORD of hosts; Behold, I will break the {h} bow of Elam, the chief of their might.

(h) Because the Persians were good archers, he shows that the thing in which they put their trust would not profit them.

35. bow-Elam was famed for its bowmen (Isa 22:6).

chief of their might-in opposition to "bow," that is, bowmen, who constituted their main strength.

49:34-39 The Elamites were the Persians; they acted against God's Israel, and must be reckoned with. Evil pursues sinners. God will make them know that he reigns. Yet the destruction of Elam shall not be for ever. But this promise was to have its full accomplishment in the days of the Messiah. In reading the Divine assurance of the destruction of all the enemies of the church, the believer sees that the issue of the holy war is not doubtful. It is blessed to recollect, that He who is for us, is more than all against us. And he will subdue the enemies of our souls.