In these verses of the Prophet's sermon, he draws a striking contrast between the fading, dying purposes of man, and the incorruptible and never-ending counsels of God! And the Apostle Peter makes a beautiful comment upon it, 1 Peter 1:23-25.
Related Commentaries of Isaiah 40:6
Isaiah 40:6-8
6 The voice said, Cry. And he said, What shall I cry? All flesh is grass, and all the goodliness thereof is as the flower of the field:
7 The grass withereth, the flower fadeth: because the spirit of the LORD bloweth upon it: surely the people is grass.
8 The grass withereth, the flower fadeth: but the word of our God shall stand for ever.