Mountains in prophecy [pdf]
Isaiah’s prophecy about making a highway in the desert is coupled with a prophecy about mountains being made low, and in many interpretations of his prophecy, the mountains are reduced to mere bumps in the road!
The voice of him that crieth in the wilderness, Prepare ye the way of the LORD, make straight in the desert a highway for our God.
Every valley shall be exalted, and every mountain and hill shall be made low: and the crooked shall be made straight, and the rough places plain:
And the glory of the LORD shall be revealed, and all flesh shall see it together: for the mouth of the LORD hath spoken it.
The message of Isaiah 40:3-5 was a theme taken up by John the Baptist, and so the prophecy is prominent in the New Testament. John dwelt in the wilderness, and he identified himself with the voice in the wilderness mentioned in Isaiah’s prophecy. Robert Lowth, bishop of London, wrote in his commentary: 
3. A voice crieth: In the wilderness—] The idea is taken from the practice of eastern monarchs, who, whenever they entered upon an expedition, or took a journey, especially through desert and unpractised countries, sent harbingers before them to prepare all things for their passage, and pioneers to open the passes, to level the ways, and to remove all impediments. The officers appointed to superintend such preparations the Latins call Stratores. “Ipse (Johannes Baptista) se stratorem vocat Messiæ, cujus esset alta et elata voce homines in desertis locis habitantes ad itinera et vias Regi mox venturo sternendas et reficiendas hortari:” Mosheim, Instituta Majora, p. 96.
Diodorus’s account of Semiramis’s marches into Media and Persia, will give us a clear notion of the preparation of the way for a royal expedition: “In her march to Ecbatane she came to the Zarcean mountain; which extending many furlongs, and being full of craggy precipices and deep hollows, could not be passed without taking a great compass about. Being therefore desirous of leaving an everlasting memorial of herself, as well as of shortening the way, she ordered the precipices to be digged down, and the hollows to be filled up; and at a great expense she made a shorter and more expeditious road, which to this day is called from her the Road of Semiramis. Afterward she went into Persia, and all the other countries of Asia subject to her dominion; and wherever she went, she ordered the mountains and precipices to be levelled, raised causeways in the plain country, and at a great expense made the ways passable:” Diod. Sic. lib. ii.
The writer of the apocryphal book called Baruch, expresses the same subject by the same images; either taking them from this place of Isaiah, or from the common notions of his countrymen: “For God hath appointed, that every high hill, and banks of long continuance, should be cast down, and vallies filled up, to make even the ground, that Israel may go safely in the glory of God;” chap. v. 7.
The Jewish, church, to which John was sent to announce the coming of Messiah, was at that time in a barren and desert condition, unfit without reformation for the reception of her king. It was in this desert country, destitute at that time of all religious cultivation, in true piety and good works unfruitful, that John was sent to prepare the way of the Lord by preaching repentance. I have distinguished the parts of the sentence according to the punctuation of the Masoretes, which agrees best both with the literal and the spiritual sense; which the construction and parallelism of the distich in the Hebrew plainly favours; and of which the Greek of the LXX and of the Evangelists is equally susceptible.
John was born in the desert of Judea, and passed his whole life in it, till the time of his being manifested to Israel. He preached in the same desert: it was a mountainous country; however, not entirely and properly a desert, for, though less cultivated than other parts of Judea, yet it was not uninhabited: Joshua (chap. xv. 61, 62.) reckons six cities in it. We are so prepossessed with the idea of John’s living and preaching in the desert, that we are apt to consider this particular scene of his preaching as a very important and essential part of his history: whereas I apprehend this circumstance to be no otherwise important, than as giving us a strong idea of the rough character of the man, which was answerable to the place of his education; and as affording a proper emblem of the rude state of the Jewish church at that time; which was the true wilderness meant by the Prophet, in which John was to prepare the way for the coming of the Messiah.
In many commentaries, the idea of making a road is connected with mountains being made low, and valleys filled. However, in making a road, only those places that are in the actual route are affected; other mountains, not in the path, would not be made low. Isaiah said every mountain would be made low. Connecting the mountains with road making seems to miss the true meaning of the prophecy. Verse 9 in the same chapter also refers to mountains; the prophet says to the mountain of Zion, “get thee up into the high mountain.”
This implies that the mountains in Isaiah’s prophecy are not literal ones. What mountains are to be made low? What high mountain was he referring to? Was Isaiah really referring to leveling bumps and hollows in a road?
I suggest that the mountains Isaiah referred to are the promises of God, which are high, and lofty, because they are spiritual revelations. They are beyond the understanding of most men. The promises of God, Jacob said, as he blessed his son Joseph, and the blessings he received, were like the mountains, and reached to “the utmost bound of the everlasting hills,” the hills that would never erode away, but are truly eternal. [Genesis 49:26] They were spiritual promises, that the promised land represents.
The prophecy of Isaiah that mountains would be made low must mean that the mysteries of these promises will be solved; their true meaning will be discovered, and prophecy will be explained so that people will understand it.
In Revelation 21:10, John was taken up into a high mountain, where he viewed the holy city. He described it as “coming down from God out of heaven.” It altitude decreases as it descends, and becomes less remote and distant from us. As the symbols in his prophecy are understood and explained, they too are made low in a figurative way. Isaiah encouraged Zion, which represents God’s people, to go up into the high mountain, just as John was taken up into a figurative high mountain, when he described the holy city, and as Ezekiel was taken up to a high mountain, when he described the visionary temple. The mountains that are to be made low are the promises and prophecies that are to be explained, and understood, the promises of the gospel.
The true meaning of the promised land is spiritual; the literal land promised to Abraham is a metaphor and a figure of the true promised land which is what the earthly Canaan represents. The promised land of the saints is the “better country” of Hebrews 11:16, and the New Covenant that Christ has brought in is founded on “better promises.”
In his discussion of verses 6-8 Lowth alluded to the contrasting views, the flesh contrasted with the spirit. The Christian one interprets the promises as eternal, while the Jews hoped for a temporal, earthly kingdom. Lowth wrote:
6—8. A voice sayeth, Proclaim—] To understand rightly this passage is a matter of importance; for it seems designed to give us the true key to the remaining part of Isaiah’s prophecies; the general subject of which is the restoration of the people and church of God. The Prophet opens the subject with great clearness and elegance: he declares at once God’s command to his messengers, (his Prophets, as the Chaldee rightly explains it,) to comfort his people in captivity, to impart to them the joyful tidings, that their punishment has now satisfied the divine justice, and the time of reconciliation and favour is at hand. He then introduces a harbinger giving orders to prepare the way for God leading his people from Babylon, as he did formerly from Egypt, through the wilderness; to remove all obstacles, and to clear the way for their passage. Thus far nothing more appears to be intended than a return from the Babylonish captivity: but the next words seem to intimate something much greater:
“And the glory of Jehovah shall be revealed; And all flesh shall see together the salvation of our God.”
He then introduces a voice commanding him to make a solemn proclamation. And what is the import of it? That the people, the flesh, is of a vain temporary nature; that all its glory fadeth, and is soon gone; but that the word of God endureth for ever. What is this, but a plain opposition of the flesh to the spirit; of the carnal Israel to the spiritual; of the temporary Mosaic economy to the eternal Christian dispensation? You may be ready to conclude, (the Prophet may be supposed to say), by this introduction to my discourse, that my commission is only to comfort you with a promise of the restoration of your religion and polity, of Jerusalem, of the temple, and its services and worship in all its ancient splendour: These are earthly, temporary, shadowy, fading things, which shall soon pass away, and be destroyed for ever; these are not worthy to engage your attention, in comparison of the greater blessings, the spiritual redemption, the eternal inheritance, covered under the veil of the former, which I have it in charge to unfold unto you. The law has only a shadow of good things; the substance is the gospel. I promise you a restoration of the former; which, however, is only for a time, and shall be done away, according to God’s original appointment: but under that image I give you a view of the latter; which shall never be done away, but shall endure for ever. This I take to be agreeable to St. Peter’s interpretation of this passage of the Prophet, quoted by him 1 Pet. i. 24, 25. “All flesh is as grass, and all the glory of man as the flower of grass. The grass withereth, and the flower thereof falleth away; but the word of the Lord endureth for ever. And this is the word which by the gospel is preached unto you.” This is the same word of the Lord of which Isaiah speaks, which hath now been preached unto you by the gospel. The law and the gospel are frequently opposed to one another by St Paul under the images of flesh and spirit: “Having begun in the spirit, are ye now made perfect by the flesh?” Gal. iii. 3.
1. Robert Lowth. Isaiah: a new translation: with a preliminary dissertation, and notes, critical, philological, and explanatory. W. Hilliard, Boston. 1834. pp. 313-314.
2. Ibid., pp. 315-316.