22. Now, Hezekiah had said. Some explain this verse as if this also had been a sign given to Hezekiah, and therefore, view it as connected with the preceding verse, and look upon it as an exclamation of astonishment. But it is more probable that in this passage the order has been reversed, as frequently takes place with Hebrew writers, and that what was spoken last is related first. Isaiah did not at the beginning say that Hezekiah had asked a sign, though the sacred history (Genesis 20:8) attests it; and therefore he adds what he had left out at the proper place.
That I shall go up. He means that it will be his chief object throughout his whole life to celebrate the name of God; for he did not desire life for the sake of living at ease and enjoying pleasure, but in order to defend the honor of God and the purity of his worship. Let us therefore remember that God prolongs our life, not that we may follow the bent of our natural disposition, or give ourselves up to luxury, but that we may cultivate piety, perform kind offices to each other, and frequently take part in the assembly of the godly and the public exercises of religion, that we may proclaim the truth and goodness of God.