Commentary by the book, Meam Loez.
"The desert and the wasteland shall rejoice; the wilderness shall exult and blossom like a lily. It shall blossom and flourish and exult, ever rejoicing and singing. The glory of the Lebanon shall be granted to it, the beauty of the Carmel and the Sharon. All shall see the glory of G-d, the beauty of our G-d." - Isaiah 35:1-2
Jerusalem and Zion, which were "desert and wasteland" throughout Jewish exile, shall rejoice upon Jewish Redemption - they shall blossom, prosper and flourish. The glory of the "Lebanon," the Temple, will be returned to her and Jerusalem will be beautiful once again. This glory and beauty will be physical - "the glory of the Lebanon and the beauty of the Carmel" - but it will also be spiritual - "the glory of G-d and the beauty of G-d." Israel's glory will be eternal, unlike the passing glory of Edom-Rome.
"Strengthen weak hands, foster failing knees. Tell the impatient, "Be strong, do not fear! For Your G-d shall come with vengeance and Divine retribution - He shall come and save you." Then, the eyes of the blind shall be opened and the ears of the deaf shall hear." - Isaiah 35:3-5
But until the Redemption, there will be those whose faith in its arrival has been weakened - the "weak handed" who wonder why it so tarries and the "failed knees" who worry over the exile's bitterness. They are the "impatient" who see only the present and cannot see ahead to the wonders of G-d. Those who can see are enjoined to encourage those who cannot, that surely, G-d will appear. Then, they too will see.
"Then the lame shall jump like deer and the tongue of the mute shall sing. For water shall break forth in the desert and streams in the wilderness." - Isaiah 35:6
The Jewish people who had been "lame," weak, throughout the exile shall now be granted great strength. As water in the desert is a miracle, so shall be their new strength. They shall be healed of all defects, both physical and spiritual, just as water can do both. Their defective understanding shall be corrected - their "eyes shall be opened" - their defective speech shall be healed - the "mutes shall sing" - and their defective behavior shall cease - the "lame shall jump."
"Arid places shall become a lake; parched areas, a spring of water. In the dwelling place where snakes rested shall be grass, reeds and rushes." - Isaiah 35:7
Water shall flow everywhere, water which is the symbol of abundance: in the most arid places, there shall be a lake, in others there shall gush a spring. And in the dry places, where snakes make their home, shall grow reeds and rushes, which grow only near bodies of water.
"There shall be there a path and a way - the holy way it shall be called. No unclean shall walk upon it and it shall be for them: (for the) wayfarers and for the fools - they shall not blunder." - Isaiah 35:8
All hindrances to reaching G-d will then be removed. The limits of human understanding will be greatly expanded - "the eyes of the blind shall be opened" - the need to toil for physical needs will then cease - "water will spring in the desert" - and man's negative inclinations will disappear - "the path to G-d shall be paved and no unclean shall walk upon it, even the fools will not blunder."
"A lion will not be found thereon, even the most brazen of beasts will not walk upon on it - they shall not be found there. The redeemed shall walk (upon it): G-d's redeemed shall return, coming to Zion with joy, with eternal rejoicing on their heads. They shall attain glee and joy, grief and woe shall disappear." - Isaiah 35:9-10
The redeemed shall return unafraid - the nations, the "brazen beasts," will not detain them. They will rejoice on their way, knowing that G-d is the One Who has redeemed them. Their joy will be boundless because they will know that this Redemption will be forever and eternal - there will be more place for grief and woe.