It is true that semantics (a branch of language dealing with the meaning of words) considers both the connotation (the feelings a word evokes in you) and the denotation (the actual meaning of the word) of words.
who is josef first of all?
[ (a.) What in me is dark
Illumine, what is low raise and support; ]
That to the highth of this great Argument
[ (b.) I may assert th' Eternal Providence, ]
The detail that helps you illustrate the idea? is that the only question? I can answer that is there anything else you need me to answer in the paragraph?