1.The wilderness and the solitary place shall be glad Here the Prophet describes a wonderful change; for having in the former chapter described the destruction of Idumaea, and having said that it would be changed into a wilderness, he now promises, on the other hand, fertility to the wilderness, so that barren and waste lands shall become highly productive. This is God’s own work; for, as he blesses the whole earth, so he waters some parts of it more lightly, and other parts more bountifully, by his blessing, and afterwards withdraws and removes it altogether on account of the ingratitude of men.

This passage is explained in various ways. I pass by the dreams of the Jews, who apply all passages of this kind to the temporal reign of the Messiah, which they have contrived by their own imagination. Some explain it as referring to Judea, and others to the calling of the Gentiles. But let us see if it be not more proper to include the whole world along with Judea; for he predicted the destruction of the whole world in such terms as not to spare Judea, and not only so, but because “the judgment of God begins at his house or sanctuary,” (1Pe 4:17,) the singularly melancholy desolation of the Holy Land was foretold, that it might be a remarkable example. Thus beginning appropriately and justly with Judea, he calls the whole world a wilderness, because everywhere the wrath of God abounded; and, therefore, I willingly view this passage as referring to Judea, and afterwards to the other parts of the world. As if he had said, “After the Lord shall have punished the wickedness and crimes of men, and taken vengeance on Jews and Gentiles, the wilderness shall then be changed into a habitable country, and the face of the whole earth shall be renewed.” Now this restoration is a remarkable instance of the goodness of God; for, when men have provoked him by their revolt, they deserve to perish altogether, and to be utterly destroyed, especially they whom he has adopted to be his peculiar people. Isaiah has his eye chiefly on the Jews, that in their distressful condition they may not faint.

Let us now see when this prophecy was fulfilled, or when it shall be fulfilled. The Lord began some kind of restoration when he brought his people out of Babylon; but that was only a slight foretaste, and, therefore, I have no hesitation in saying that this passage, as well as others of a similar kind, must refer to the kingdom of Christ; and in no other light could it be viewed, if we compare it to other prophecies. By “the kingdom of Christ,” I mean not only that which is begun here, but that which shall be completed at the last day, which on that account is called “the day of renovation and restoration,” (Act 3:21;) because believers will never find perfect rest till that day arrive. And the reason why the prophets speak of the kingdom of Christ in such lofty terms is, that they look at that end when the true happiness of believers, shall be most fully restored.

After having spoken of dreadful calamities and predicted the lamentable ruin of the whole world, the Prophet comforts believers by this promise, in which he foretells that all things shall be restored. This is done by Christ, by whom alone they can be renewed and made glad; for he alone renews everything, and restores it to proper order; apart from him there can be nothing but filth and desolation, nothing but most miserable ruin both in heaven and in earth. But it ought to be carefully observed, that the world needed to be prepared by chastisements of this nature, in order that it might be fit and qualified for receiving such distinguished favor, and that the grace of Christ might be more fully manifested, which would have been concealed if everything had remained in its original state. It was therefore necessary that the proud and fierce minds of men should be east down and subdued, that they might taste the kindness of Christ, and partake of his power and strength.

2.Flourishing it shall flourish He describes more fully how great, will be the effect of the grace of Christ, by whose power and might those places which had been overgrown with filthy and noxious weeds “flourish” exceedingly and regain their vigor. This repetition is used for the sake of amplification. The doubling of the word “flourish” may be taken in two senses; either to denote the prolongation of time in incessant vegetation; as if he had said, “It shall not flourish with a passing or fading blossom, so as to return immediately to the foul condition in which it once was, but with a continual, uninterrupted, and long-continued bloom, which can never fade or pass away;” or to denote the increase and daily or yearly progress of improvement; for Christ enriches us in such a manner as to increase his grace in us from day to day.

The glory of Lebanon, the beauty of Carmel and Sharon These metaphors display more fully the fertility already described; for the Prophet is not satisfied with saying that where formerly there was a gloomy wilderness smiling fields will be seen, and that dry places will be clothed with the beauty of flowers, but adds that there will be such luxuriant beauty as “Lebanon, Carmel, and Sharon” were celebrated for possessing. Though Carmel denotes a cultivated and fertile field, yet here it is a proper name, like the other two. We have seen in other passages ²² that these mountains were highly celebrated, and throughout the whole of Judea held the undisputed preeminence both for delightfulness and for abundance of fruits.

They shall see the glory of Jehovah What he had formerly spoken metaphorically he now explains clearly and without a figure. Till men learn to know God, they are barren and destitute of everything good; and consequently the beginning of our fertility is to be quickened by the presence of God, which cannot be without the inward perception of faith. The Prophet undoubtedly intended to raise our minds higher, that we may contemplate the abundance and copiousness of heavenly benefits; for men might be satisfied with bread and wine and other things of the same kind, and yet not acknowledge God to be the author of them, or cease to be wretched; and indeed men are often blinded and rendered more fierce by enjoying abundance. But when God makes himself visible to us, by causing us to behold his glory and beauty, we not only possess his blessings, but have the true enjoyment of them for salvation.

3.Strengthen ye the weak hands We might explain this passage generally, as if he had said, “Let those who have feeble hands strengthen them, let; them whose knees tremble and totter compose and invigorate their hearts.” But the following verse shews that the whole of this passage relates to the ministers of the word; for he addresses the teachers of the Church, and enjoins them to exhort, arouse, and encourage weak men whose hearts are broken or east down, that they may be rendered more firm and cheerful. This exhortation is seasonably introduced, because he saw that so many tokens of God’s anger, of which he had spoken, could not do otherwise than fill even the strongest minds with alarm and dread; for, seeing that we are always enfeebled by adversity, when God himself proclaims what may be called open war against us on account of our sins, who would not tremble? But the Prophet commands that they who are cast down and almost lifeless shall be enlivened, and the manner of doing it is explained by him in the following verse.

4.Say to them that are faint hearted That strength of which he spoke is breathed into our hearts by God through his word, as “by faith alone we stand” (2Co 1:24) and live; and therefore he adds the promise of grace yet to come.

Behold, your God will come First, it ought to be observed that God does not wish that his grace should remain concealed and unknown, but rather that it should be proclaimed and imparted, that they who totter and tremble may compose and invigorate their hearts. And this is one method by which our hearts may be cheered amidst heavy distresses; for if we are not supported by the word of the Lord, we must faint and despair. This, then, is the office assigned to the teachers of the word, to raise up them that are fallen down, ²³ to strengthen the feeble, to upheld the tottering.

We ought also to observe how great is the efficacy of the word in “invigorating the feeble hands and strengthening the tottering knees;” for if it had not been a powerful instrument in communicating this strength, the Prophet would never have spoken in this manner; and, indeed, if God struck only our ears by his word, and did not pierce our hearts, these words would have been spoken in vain. Since, therefore, the Lord assigns this office to the word, let us know that he also imparts this power to it, that it may not be spoken in vain, but may inwardly move our hearts, not always indeed or indiscriminately, but where it pleases God by the secret power of his Spirit to work in this manner. And hence we infer that the same word makes us disposed to obey him; for otherwise we shall be indolent and stupid; all our senses shall fail, and we shall not only waver, but shall be altogether stupified by unbelief. We, therefore, need to receive aid from the Lord, that the removal of our fear and the cure of our weakness may enable us to walk with agility.

Fear not; behold, your God will come This warning deeply fixed in our minds will banish slothfulness. As soon as men perceive that God is near them, they either cease to fear, or at least rise superior to excessive terror.

“Be not anxious,” says Paul, “for the Lord is at hand.” (Phi 4:5.)

On this subject we have spoken largely on other occasions; and the Apostle to the Hebrews appears to allude to this passage, when, after having charged them not to be wearied and faint-hearted, he quotes the words of the Prophet. (Heb 12:3.) Yet he directs this discourse to every believer, that they may be excited to perseverance, and because they have many struggles to maintain, may advance steadfastly in their journey. Nor is it superfluous that he adds your God; for if we do not know that he is our God, his approach will produce terror, instead of giving cause of joy. Not the majesty of God, which is fitted to humble the pride of the flesh, but his grace, which is fitted to comfort the fearful and distressed, is here exhibited; and, therefore, it is not without reason float he is represented as a guardian, to shield them by his protection.

If it be objected that he brings terror when he comes to take vengeance, I reply that this vengeance, is threatened against wicked men and enemies of the Church. To the latter, therefore, he will be a terror, but to believers he will be a consolation; and accordingly he adds that he will come to save them, because otherwise it might be objected, “What is it to us if our enemies be punished? What good does it do to us? Must we take delight in the distresses of enemies?” Thus he expressly declares that it will promote our “salvation;” for the vengeance which God takes on wicked men is connected with the salvation of the godly. In what manner the godly are delivered from anxiety and dread by the favor of God and by the expectation of his aid, has been explained at a former passage). ²⁴ (Isa 7:4.) At present it ought to be observed, that God is prepared and armed with vengeance, that believers may learn to lean on his aid, and not to fancy some deity unemployed in heaven. Such is also the object of the repetition of the words, “he will come;” because distrust is not all at once banished from the hearts of men.

The end of the verse may either be rendered, God himself will come with a recompense, or He will come with the recompense of God; but as the meaning is the same, the reader may make his choice Yet if it be thought preferable to view אלהים (elohim) as in the genitive case, “of God,” then by “the recompense of God” is emphatically meant that which belongs peculiarly to God, that believers may be fully convinced that he is a “rewarder” as truly as he is God. ²⁵

After the desolations left by the tribulation catastrophes, the earth's geography and climatology will have been restored to pristine antediluvian conditions. Originally there were no deserts or other uninhabitable regions, for all was "very good" (Gen 1:31). At least in some measure, these conditions will be restored during the coming kingdom age on earth."

This is good advice for the believer in any age (Job 4:3, Job 4:4; Heb 12:12)."

wilderness : Isa 29:17, Isa 32:15, Isa 32:16, Isa 40:3, Isa 51:3, Isa 52:9, Isa 52:10; Eze 36:35

be : Psa 48:11, Psa 97:8; Rev 19:1-7

desert : Isa 4:2, Isa 27:6, Isa 55:12, Isa 55:13, Isa 61:10,Isa 61:11, Isa 66:10-14; Hos 14:5, Hos 14:6

and rejoice : Isa 42:10-12, Isa 49:13, Isa 55:12, Isa 55:13; 1Ch 16:33; Psa 65:12, Psa 65:13, Psa 89:12, Psa 96:11-13; Psa 98:7-9, Psa 148:9-13; Zec 10:7; Rom 10:15, Rom 15:10

the glory : Isa 33:9, Isa 41:19, Isa 60:13, Isa 60:21, Isa 61:3, Isa 65:8-10; Psa 72:16; Hos 14:6, Hos 14:7

the excellency : Isa 60:13; Eze 34:25, Eze 34:26; Amo 9:13-15; Mic 7:14, Mic 7:15; Zep 3:19, Zep 3:20; Zec 14:20,Zec 14:21; Act 4:32, Act 4:33

they shall : Isa 6:3, Isa 40:5, Isa 60:1-3, Isa 60:19, Isa 66:18, Isa 66:19; Exo 33:18, Exo 33:19; Psa 50:2, Psa 72:19, Psa 97:6; Psa 102:15, Psa 102:16; Hab 2:14; Joh 12:41, Joh 17:24; 2Co 3:18, 2Co 4:6; Rev 21:23

Isa 40:1, Isa 40:2, Isa 52:1, Isa 52:2, Isa 57:14-16; Jdg 7:11; Job 4:3, Job 4:4, Job 16:5; Luk 22:32, Luk 22:43; Act 18:23; Heb 12:12

fearful : Heb. hasty, Isa 28:16, Isa 32:4 *marg. Psa 116:11; Hab 2:3

Be strong : Isa 44:2; Jos 1:6, Jos 1:7; 1Ch 28:20; Dan 10:19; Hag 2:4; Eph 6:10; 2Ti 2:1

fear not : Isa 41:10-14, Isa 43:1-6, Isa 54:4, Isa 54:5; Zep 3:16, Zep 3:17; Rev 2:10

behold : Isa 25:9, Isa 26:20,Isa 26:21, Isa 34:8, Isa 40:9, Isa 40:10, Isa 52:7-10, Isa 61:2, Isa 66:15; Deu 32:35-43; Psa 50:3; Hos 1:7; Zec 2:8-10; Mal 3:1; Mat 1:21-23; Luk 21:28; Heb 9:28, Heb 10:37, Heb 10:38; Jam 5:7-9; Rev 1:7, Rev 22:20