Isaiah is 'undone' by the awesomeness of God and hears the question, 'Who will go?' When Isaiah says, 'I will,' he's told his message will go unheeded until the land is desolate. Phew. That's not what we expect, and it's not a job assignment that delights the ego. We want to serve God and see the lands explode with His glory. We want our work to reward us with success. Faith in God's ultimate working out of His perfect plan must sustain us. We do not serve ourselves or man; we must constantly remember God's exalted being.
Here's a beautiful word picture that brings a smile (and joyful excitement) to my heart: