The prophet’s duty was plain—he was to lift his voice against the prevailing evils. But he dreaded to undertake the work without some assurance of hope. “Lord, how long?” he inquired. Verse 11. Are none of Your chosen people ever to repent and be healed? RR 113.6
His mission was not to be completely fruitless, yet the evils that had been multiplying for generations could not be removed in his day. He must be a patient, courageous teacher—a prophet of hope as well as of doom. A remnant would be saved. To bring this about, he was to deliver messages of pleading to the rebellious nation. RR 114.1
The ten tribes of the northern kingdom were soon to be scattered among the nations. The destroying armies of hostile nations were to sweep over the land again and again. Even Jerusalem was finally to fall and Judah to be carried away captive. Yet the Promised Land was not to remain forsaken forever. The assurance of the heavenly messenger to Isaiah was: RR 114.2
“A tenth will be in it,
And will return and be for consuming,
As a terebinth tree or as an oak,
Whose stump remains when it is cut down,
So the holy seed shall be its stump.” Verse 13 RR 114.3
This assurance brought courage to Isaiah. He had seen the King, the Lord of hosts. He had heard the song of the seraphim, “The whole earth is full of His glory!” Verse 3. He had the promise that the convicting power of the Holy Spirit would accompany the messages of Jehovah, and the prophet was braced for the work before him. Throughout his long, difficult mission he carried the memory of this vision. For sixty years or more he stood as a prophet of hope, predicting the future triumph of the church. RR 114.4