The 1st amendment doesn't say anything about expression. Speech is the articulation of words whether its verbal,written or sign languaged.
Congress shall make no law respecting an establishment of religion, or prohibiting the free exercise thereof; or abridging the freedom of
speech
American Heritage Dictionary Entry: speech
1.
a. The faculty or act of speaking.
b. The faculty or act of expressing or describing thoughts, feelings, or perceptions by the articulation of words.
2.
a. What is spoken or expressed, as in conversation; uttered or written words: seditious speech.
b. A talk or public address, or a written copy of this: The senator gave a speech.
3.
a. The language or dialect of a nation or region: American speech.
b. One's manner or style of speaking: the mayor's mumbling speech.
4. The study of oral communication, speech sounds, and vocal physiology.
American Heritage Dictionary Entry: expression
1. The act of expressing, conveying, or representing in words, art, music, or movement; a manifestation: an expression of rural values.
2. Something that expresses or communicates: Let this plaque serve as an expression of our esteem.
3. Mathematics A symbol or combination of symbols that represents a quantity or a relationship between quantities.
4. The manner in which one expresses oneself, especially in speaking, depicting, or performing.
5. A particular word or phrase: "an old Yankee expression ... 'Stand up and be counted'" (Charles Kuralt).
6. The outward manifestation of a mood or a disposition: My tears are an expression of my grief.
7. A facial aspect or a look that conveys a special feeling: an expression of scorn.
8. The act of pressing or squeezing out.
9. Genetics The act or process of expressing a gene.