Lift up your eyes to the heavens, and look upon the earth beneath: for the heavens shall vanish away like smoke, and the earth shall wax old like a garment, and they that dwell therein shall die in like manner: but my salvation shall be for ever, and my righteousness shall not be abolished. My salvation shall be for ever - Aben Ezra says, From this verse divines have learnt the immortality of the soul. Men shall perish as the earth does, because they are formed from it; but they who are filled with the salvation of God shall remain for ever. See Kimchi.
Related Commentaries of Isaiah 51:6
Isaiah 51:6
6 Lift up your eyes to the heavens, and look upon the earth beneath: for the heavens shall vanish away like smoke, and the earth shall wax old like a garment, and they that dwell therein shall die in like manner: but my salvation shall be for ever, and my righteousness shall not be abolished.