Isaiah 6:7

And he laid it upon my mouth. — So Jehovah “touched the mouth” of Isaiah’s great successor (Jeremiah 1:9); but not in that case with a “coal from the altar.” That prophet, like Moses (Exodus 4:10), had felt only or chiefly the want of power (“Alas! I cannot speak), and power was given him. Isaiah desired purity, and his prayer also was answered.

Thine iniquity is taken away, and thy sin purged. — The clauses express the two elements of the great change which men, according to their varying systems, have called Conversion, the New Birth, Regeneration; but which is at all times a necessary stage in the perfecting of the saints of God. Pardon and purity are the conditions alike of the prophet’s work and of the completeness of his own spiritual life.