This is the eighth in a series of postings looking at the meaning of Isaiah 6 for today; it began (here).
The first part of Isaiah 6 is a favorite among preachers, esp. those who want to motivate their congregation in one way or another. It starts with the grand vision, as we've seen, and it ends in verse 8 with God asking, "Who is willing to be my messenger," and Isaiah famously responding, "OK, Lord, I'll go." Unlike other Old Testament figures called by God—Moses and Jeremiah always come to mind—Isaiah didn't hesitate even though God didn't specifically address him with the fateful question. Isaiah, thus, is the epitome of commitment, a wonderful object lesson for all of us—so long as we don't read beyond verse 8. The rest of the chapter is something else again.
Hold that thought while we digress for a moment. Commentators wrestle with the placing of Isaiah's call in chapter 6. Logically, it should be at the very beginning of the book. One theory (a good one so far as I can see) is that the whole call including verses 9 and following only makes sense if the reader understands the actual situation facing the Hebrew people in Isaiah's time. Without going into all the details (see Isaiah 1-5), Isaiah's actual call was to preach doom and gloom, pronounce judgement, and issue dire warnings of a dark future.
In that context, verses 9 and following make more sense. Once Isaiah volunteers to be God's prophet, God basically charges Isaiah to preach a message that will fail to communicate so that the people will not escape the doom that awaits them. When Isaiah asks, "How long am I supposed to preach this message and how long will the people stand under judgment?" God answers, "Until there's nothing left but a stump." The destruction of Judah will be all but total, leaving only a metaphorical stump. Modern-day preachers seldom venture into the hostile territory of verses 9 and following. It is a whole lot less inspiring than what comes before. It's so bad that I can't even end this posting with an "Amen." Stay tuned.