I think you're making this a little bit more complicated than what it is.
"And whoever walks a furlong without sympathy walks to his own
funeral drest in his shroud."
The author has already identified the gender in this sentence, and he is conveying that the gender is male in his poem. Now let's go back to your previous example of "They." I think this is the best way to describe this word in a sentence with a definition.
Picture you're outside of a store, and you and someone with you see a person in the store, but you don't know the gender. One of you may tell the other to go see if they may help you. Once you know the gender, you can use the word he or she.