The form of the prophet's confession, _uncleanness of lips_, will not surprise us as far as he makes it for himself. As with the disease of the body, so with the sin of the soul; each often gathers to one point of pain. Every man, though wholly sinful by nature, has his own particular consciousness of guilt. Isaiah being a prophet felt his mortal weakness most upon his lips. The inclusion of the people, however, along with himself under this form of guilt, suggests a wider interpretation of it. The lips are, as it were, the blossom of a man. _Grace is poured upon thy lips, therefore God hath blessed thee for ever. If any man offend not in word, the same is a perfect man, able to bridle the whole body also._ It is in the blossom of a plant that the plant's defects become conspicuous; it is when all a man's faculties combine for the complex and delicate office of expression that any fault which is in him will come to the surface. Isaiah had been listening to the perfect praise of sinless beings, and it brought into startling relief the defects of his own people's worship. Unclean of lips these were indeed when brought against that heavenly choir. Their social and political sin--sin of heart and home and market--came to a head in their worship, and what should have been the blossom of their life fell to the ground like a rotten leaf beneath the stainless beauty of the seraphs' praise.
While the prophet thus passionately gathered his guilt upon his lips, a sacrament was preparing on which God concentrated His mercy to meet it. Sacrament and lips, applied mercy and presented sin, now come together. _Then flew unto me one of the seraphim, and in his hand a glowing stone--with tongs had he taken it off the altar--and he touched my mouth and said, Lo, this hath touched thy lips, and so thy iniquity passeth away and thy sin is atoned for._