Isaiah continues his vivid description of what was wrong with God’s people and what God will do to those who do not change their ways.  The keys to the purpose of this sermon lies in vv. 7, 16, 24b.  Here we find an implied call to live lives of justice, righteousness, holiness, obedience to God’s law and word.  Without this kind of life, one cannot hope to escape the terrible woes to the wicked (vv. 8, 11, 18, 20, 21, 22).  The Gospel creates this kind of people and the Gospel can be seen in v. 7 where Jesus receives the ultimate injustice, His own blood is shed, and He cries out to the Father.