1286. That a "lip" signifies doctrine, is evident from the following passages in the Word. In Isaiah:
The seraphim cried and said, Holy, holy, holy, Jehovah of Armies. And the prophet said, Woe is me! for I am cut off, because I am a man of unclean lips, and I dwell in the midst of a people of unclean lips; for mine eyes have seen the King, Jehovah of Armies. Then flew one of the seraphim unto me, and he touched my mouth, and said, Lo, this hath touched thy lips; and thine iniquity is taken away, and thy sin is expiated (Isa. 6:3, 5-7).
"Lips" here denote the interior things of man, thus internal worship, from which is adoration, as is here represented with the prophet. That his lips were touched, and that thus his iniquity was taken away and his sin expiated, anyone may see was a representative of interior things that are signified by the "lips," which are things of charity and its doctrine.
Jehovah shall smite the earth with the rod of His mouth, and with the breath of His lips shall He slay the wicked (Isa. 11:4).
In the internal sense this does not mean that Jehovah smites with the rod of His mouth, and slays the wicked with the breath of His lips, but that a wicked man does this to himself; "the breath of the lips" is doctrine, which with the wicked is false. Again:
I create the increase of the lips, peace, peace, to him that is far off, and to him that is near, saith Jehovah; and I heal him (Isa. 57:19).
"The increase of the lips" denotes doctrine.
 In Ezekiel:
Son of man, go, get thee unto the house of Israel, and speak My words unto them. For thou art not sent to a people deep of lip, and heavy of tongue, but to the house of Israel; not to many peoples deep of lip and heavy of tongue, whose words thou canst not understand. If I had sent thee to them, would they not have hearkened unto thee? But the house of Israel will not hearken unto thee, for they will not hearken unto Me, for all the house of Israel are of a hardened forehead, and hard of heart (Ezek. 3:4-7).
"Deep of lip" is predicated of the nations which although in falsity of doctrine were yet in charity, and are therefore said to "hearken;" but they who are not in charity are said to be of "a hardened forehead, and a hard heart."
 In Zephaniah:
Then will I turn to the people with a clear lip, that they may all call upon the name of Jehovah, to serve Him with one shoulder (Zeph. 3:9).
"A clear lip" manifestly denotes doctrine. In Malachi:
The law of truth was in his mouth, and perversity was not found in his lips. For the priest's lips should keep knowledge, and they should seek the law at his mouth; for he is the angel of Jehovah of Armies (Mal. 2:6-7).
This is said of Levi, by whom the Lord is represented; "lips" denote doctrine from charity. In David:
Who say, With our tongue will we prevail; our lips are with us (Ps. 12:4).
Here "lips" denote falsities. Again:
My soul shall be satisfied as with marrow and fatness; and my mouth shall praise Thee with lips of songs (Ps. 63:5).
In that day there shall be five cities in the land of Egypt speaking with the lip of Canaan, and swearing to Jehovah of Armies (Isa. 19:18)
"lip" denotes doctrine.