I will go before thee, and make the crooked places straight: I will break in pieces the gates of brass, and cut in sunder the bars of iron: The crooked places "The mountains" - For הדורים hodurim, crooked places, a word not easily accounted for in this place, the Septuagint read הררים hararim, τα ορη, the mountains. Two MSS. have הדרים hadarim, without the ו vau, which is hardly distinguishable from the reading of the Septuagint. The Divine protection that attended Cyrus, and rendered his expedition against Babylon easy and prosperous is finely expressed by God's going before him, and making the mountains level. The image is highly poetical: -
At vos, qua veniet, tumidi subsidite montes,
Et faciles curvis vallibus este viae.
Ovid, Amor. 2:16.
"Let the lofty mountains fall down,
and make level paths in the crooked valleys."
The gates of brass "The valves of brass" - Abydenus, apud, Euseb. Praep. Evang. 9:41, says, that the wall of Babylon had brazen gates. And Herodotus, i, 179. more particularly: "In the wall all round there are a hundred gates, all of brass; and so in like manner are the sides and the lintels." The gates likewise within the city, opening to the river from the several streets, were of brass; as were those also of the temple of Belus. - Herod. i., 180, 181.