I would say that the lines which show us how desperate the poet is are the following:
"... helpless in my throes, Biting my truant pen, beating myself for spite--"
As you can see here, the poet says he is helpless, meaning that he cannot find inspiration to write what he wants to write. Therefore he is desperate for some inspiration, which is why he is biting his truant pen in order to show how anxious he is to get his inspiration back.
I would say the names of people and places.
The author of "Zlateh the Goat", Isaac Bashevis Singer, was a Polish Jewish author. In the story, not only are the main characters Jewish, but also the story is set around Hanukkah (and contains references to specific Hanukkah traditions and preparations), an important Jewish holiday. You should also note that the text was initially written in Yiddish, which is a dialect central to Jewish (especially Ashkenazi Jewish) culture.
