NOTES for Isa 6:1-13
It must not have been by chance that the Lord appeared to the prophet in the year of the king's death. Earthly rulers can change, but the Heavenly King remains forever.
The burning coal with which the seraph touched Isaiah's lips had been taken from the altar that burned before the face of the Lord. Isaiah's prophetic ministry became a participation in sacrifice, just as every true ministry to the Lord is sacrificial. It was the sacrificial coal that cleansed the prophet and enabled him to volunteer boldly to go into service.
But what the prophet must say to the people is hard. He must speak about the fact that people have lost the ability to hear and see, so that addressing them with words of truth and wisdom is pointless. But if that is so, why should the prophet go out to preach at all?
Apparently, so that the words would still sink deep into at least some of the listeners, so that they would be heard by at least a few people. And will those few not be among the remnant that, after all the disasters, will put out a new shoot?