381 About that time Hezekiah became deathly ill, and the prophet Isaiah son of Amoz went to visit him. He gave the king this message: "This is what the Lord says: 'Set your affairs in order, for you are going to die. You will not recover from this illness.'" 2 When Hezekiah heard this, he turned his face to the wall and prayed to the Lord, 3 "Remember, O Lord, how I have always been faithful to you and have served you single-mindedly, always doing what pleases you." Then he broke down and wept bitterly. 4 Then this message came to Isaiah from the Lord : 5 "Go back to Hezekiah and tell him, 'This is what the Lord, the God of your ancestor David, says: I have heard your prayer and seen your tears. I will add fifteen years to your life, 6 and I will rescue you and this city from the king of Assyria. Yes, I will defend this city. 7 "'And this is the sign from the Lord to prove that he will do as he promised: 8 I will cause the sun's shadow to move ten steps backward on the sundial of Ahaz!'" So the shadow on the sundial moved backward ten steps.
Matthew Henry's Commentary on Isaiah 38:1-8
Commentary on Isaiah 38:1-8
(Read Isaiah 38:1-8)
When we pray in our sickness, though God send not to us such an answer as he here sent to Hezekiah, yet, if by his Spirit he bids us be of good cheer, assures us that our sins are forgiven, and that, whether we live or die, we shall be his, we do not pray in vain. See 2 Kings 20:1-11.