[...] the textual [component], has an enabling function, that of creating text, which is language in operation as distinct from strings of words or isolated sentences and clauses. It is this component that enables the speaker to organize what he is saying in such a way that it makes sense in the context and fulfils its function as a message.
- Halliday (1973), a pag.66

The textual component is concerned with the creation of text; it expresses the structure of information, and the relation of each part of the discorse to the whole and to the setting.
- Halliday (1973), a pag.99