“Every valley shall be lifted (up),
and every mountain and hill shall be made low;
and the heel shall be (made in)to a straight (place),
and the ridges split (in)to a level (place).”
The imagery here is relatively straightforward, even if the actual vocabulary is a bit problematic for us today. In the first couplet, we have juxtaposed the raising up of low spots and the lowering of high spots, in order to make a clear and level path for travel. The reference to mountains and valleys gives to the road-construction motif a cosmic dimension. A vast geographical terrain is involved, and we might compare it to the engineering feats involved in the creation of modern railways and highways, so that they run through mountains and over lowlands both. There is also a bit of hyperbolic exaggeration involved, as is typical of such descriptions by rulers of their building projects. Baltzer (p. 54) mentions a royal inscription by the Babylonian king Nebuchadnezzar II:
“What no former had done (I achieved): I cut through steep mountains, I split rocks, opened passages and (thus) I constructed a straight road for the (transport of the) cedars.”
He also notes the description in Herodotus (5.52-54) of the Persian royal highway (“the way of the king”, h( o(do\$ h( basilikh/) from Sardis to Susa.
The second couplet in verse 4 is rather more difficult to translate. The word bq)u* literally means “heel”, presumably in the sense of hilly or knotted terrain (with bumps and ridges). In the first couplet the emphasis was on height, here the idea is roughness—bumps and obstructions which, if navigated, would result in a twisting and winding road. There may be an intentional play on the name of Jacob (= Israel), bq)u&y~, traditionally explained as denominative from the root bqu, i.e., “take by the heel” (cf. Gen 25:25-26, but compare Gen 27:36). The negative ethical connotation of “grabbing the heel” should be understood here in light of the crooked/straight juxtaposition. This contrast was established in verses 2 and 3; the “crookedness” (/ou*) of the people has been rectified (through the punishment of the Exile), and they are now called upon to be “straight” (vb rv^y`) again.
In the final line, the corresponding noun is the plural <ys!k*r=, which is difficult to translate, but, in geographical terms, refers to hills or mounds that are bound together into a ridge (i.e., “ridges”). The idea is of a tight hill-formation that needs to be broken up—literally “split”, as indicated by the root uqb. In the context here, the noun hu*q=b! signifies a level place after such a ridge has been split in two, allowing a roadway to pass through.
On the one hand, verses 3-4 refer to a real road, in the sense that there will be an actual route (or routes) taken by the exiles on their return home. Yet, on the other hand, the language and imagery is symbolic, referring to the return itself—that is, the deliverance of the people and their restoration into a new covenant bond with YHWH. The road built in the desert signifies this deliverance, a ‘new Exodus’ for God’s people, brought about by the royal command of YHWH Himself. This theological aspect becomes clear in verse 5, where the ultimate purpose of this royal highway in the desert is exclaimed.
“And (the) weight of YHWH will be uncovered,
and all flesh as one will see (it),
for (the) mouth of YHWH has spoken.”
The purpose of this road is so that the majesty (lit. “weight”, dobK*) of YHWH will be revealed (“uncovered”, vb hl*G`), for all the world to see. As I discussed in the previous note, the wording in verse 3 can be taken to mean that the road will serve, quite literally, as a place for God to travel. There is a strong eschatological aspect to the Deutero-Isaian poems, and this emphasis begins here in the opening poem. While not so pronounced as in later Jewish tradition, we are still dealing with the idea that the restoration of Israel marks the beginning of a New Age, and the end of the old order of things on earth (and among the nations). When YHWH appears to restore the fortunes of His people (and bring them back to their Promised Land), it correspondingly means judgment for the rest of the nations. The seed of this Judgment-theme is introduced here in verse 5.
There is also a bit of wordplay involving the verb hl*G`, which has the fundamental meaning “uncover” —that is, to remove a covering. In both a literal and figurative sense, the same root is also used for the experience of captivity and exile (in the related nouns hl*oG and tWlG`). The captive is stripped of honor and dignity, etc, and even (quite literally) may have their garments removed; and then they themselves are “removed” (exiled) to another land. It is through this nifty wordplay (almost impossible to capture in translation) that the revelation of YHWH’s majesty is made to relate most clearly to the captivity (hl*oG) of Judah. God’s majesty is demonstrated (and declared) in His bringing an end to the captivity, and providing a way by which the captives can return home.
The entirety of verse 1-5 comprises a message, a word spoken by YHWH. This is clear from the way that verse 5 concludes (“the mouth of YHWH has spoken”), but the theme is also expounded further in vv. 6-8, which we will examine in the next note.
References above marked “Baltzer” are to Klaus Baltzer, A Commentary on Isaiah 40-55, transl. by Margaret Kohl, Hermeneia Commentary series (Fortress Press: 2001).