6985. Because heavy of mouth and heavy of tongue am I. That this signifies that the voice and speech from the Divine are not heard or perceived, is evident from the signification of "mouth," as being voice; and from the signification of "tongue," as being speech. By "mouth," is signified voice, because it is the organ of the voice; and by "tongue" is signified speech, because it is the organ of speech. The difference between voice and speech is plain to everyone, also that "to be heard" is said of the voice, and "to be perceived" of speech. This cannot be expressed in the historic sense of the letter, where Moses is spoken of as a man, and who could speak, but with difficulty, otherwise than by being "heavy of mouth and heavy of tongue." But when this passes into the internal sense, it is perceived by the angels as being said in respect to the subject treated of; and when it is said of the Divine, it is perceived that the voice proceeding thence cannot be heard nor the speech be perceived immediately, but mediately through spirits, according to what was said above (n. 6982).