John Calvin Commentary Isaiah 40:8

"The grass withereth, the flower fadeth; but the word of our God shall stand forever." — Isaiah 40:8 (ASV)

The grass withereth. This repetition is again added for the purpose of bringing to nothing the glory of the flesh, but at the same time, it contains within itself a highly valuable consolation: that God, when he has cast down his people, immediately raises them up and restores them. The context, therefore, runs as follows: The grass indeed withereth and perisheth, but the word of the Lord endureth for ever. After learning how empty and destitute we are of all blessings, and how transitory and fading is the glory of the flesh, our only remaining consolation—by which we may be raised up by the word of the Lord as by an outstretched hand—is this: though we are frail and fading, the word of the Lord is durable and eternal. In short, the life we need is offered to us from another source.

But the word of our God shall stand for ever. This passage encompasses the whole Gospel in few words, for it consists of an acknowledgment of our misery, poverty, and emptiness, so that, being sincerely humbled, we may fly to God, by whom alone we shall be perfectly restored. Therefore, let people not faint or be discouraged by the knowledge of their nakedness and emptiness, for the eternal word is presented to them, by which they may be abundantly supported and upheld.

We are also taught that we should not seek consolation from any other source than from eternity, which should not be sought anywhere else than in God, since nothing that is firm or durable will be found on the earth.

Nothing is more foolish than to rest satisfied with the present state, which we see to be fleeting. Every person is mistaken who hopes to be able to obtain perfect happiness until he or she has ascended to God, whom the Scripture calls eternal, so that we may know that life flows to us from him.

Indeed, he adopts us to be his children on this condition: to make us partakers of his immortality.

But this would be of no use if the manner of seeking him were not pointed out. Therefore, he presents the word, from which we must not in any respect turn aside.

For if we make the smallest departure from it, we shall be involved in strange labyrinths and shall find no way of extricating ourselves.

Now, the word is called eternal, not merely in itself, but in us; and this should be particularly observed, because otherwise we could obtain no consolation.

And so Peter, a faithful interpreter of this passage, applies it to us when he says that we are regenerated by this incorruptible seed, that is, he says, by the word which is preached (1 Peter 1:23, 25).

From this we infer, as I mentioned a little before, that life is prepared for the dead who shall come thirsting to the fountain that is presented to them; for the power that is hidden in God is revealed to us by the word.