Isaiah 38:15
What shall I say? he hath both spoken unto me, and himself hath done it: I shall go softly all my years in the bitterness of my soul. What shall I say? he hath both spoken unto me, and himself hath done it: I shall go softly all my years in the bitterness of my soul.
Isaiah 38:15 belongs to Hezekiah's song after the God of heaven granted him a new lease of life from sickness, with the turning back of the shadow ten degrees on the sundial given as the sign of that healing. Its opening acknowledges that God had both spoken concerning his illness and acted to deliver and heal him, carrying out what He had promised. In response Hezekiah resolves to spend the rest of his years walking humbly, carefully, and gratefully, ever mindful of the bitterness of his suffering, illness, and nearness to death.
The testimony presents God as the living God, the upholder of all created things and the supreme sovereign, who spared Hezekiah's life by favor when all other hope had fled. The sign of the healing was observed by wise men devoted to astronomy in the Tigris and Euphrates valleys, and when Merodach-baladan learned it was a sign to the king of Judah he sent ambassadors to congratulate Hezekiah on his recovery and to learn more of the God who had done it. The deliverance gave Hezekiah the opportunity and duty to extol the living God to the seekers after truth from the plains of Chaldea, telling them of God's favor so they would acknowledge His supreme sovereignty.
Faithfulness in that witness could have brought momentous transformations. His healing shows that trust in God does not rule out practical treatment, for God directed the application of a fig in his restoration, teaching that people may trust God while using remedies and working in harmony with natural laws.