That is what it means.
No, the voice of God does not come to man by letters on a page - but through the LIPS of prophets and messengers. Don't forget that. The Bible is full of such men...
Hebrews 1:1 ¶God, who at sundry times and in divers manners spake in time past unto the fathers by the prophets,
2 Hath in these last days spoken unto us by his Son, whom he hath appointed heir of all things, by whom also he made the worlds;
3 Who being the brightness of his glory, and the express image of his person, and upholding all things by the word of his power, when he had by himself purged our sins, sat down on the right hand of the Majesty on high;
you reply That is what it means.
Why would an angel burn the lips of Isaiah, rather than his writing hand? I am beginning to wonder about some of the responses you have given me recently...