What are some repeating words, phrases, or character actions in the "Tell-Tale Heart" by Edgar Allen Poe?

I'll pick words and phrases that are repeated throughout "The Tell-Tale Heart."  The narrator, very early on in the story, tries to establish his sanity.  In fact, the narrator reminds the reader throughout the story that he is not crazy.  The words "mad" and "madness" are used a total of seven times throughout the text.  For example, from the opening paragraph:

I heard all things in the heaven and in the earth. I heard many...

I'll pick words and phrases that are repeated throughout "The Tell-Tale Heart."  The narrator, very early on in the story, tries to establish his sanity.  In fact, the narrator reminds the reader throughout the story that he is not crazy.  The words "mad" and "madness" are used a total of seven times throughout the text.  For example, from the opening paragraph:

I heard all things in the heaven and in the earth. I heard many things in hell. How, then, am I mad?

How is he not crazy?  The man just admitted to being able to hear stuff from heaven and hell.  That sounds crazy to me.  He continues to attempt to prove his sanity by telling the reader that he couldn't be consumed with madness, because he was really careful about stalking and killing the other guy.  

Now this is the point. You fancy me mad. Madmen know nothing. But you should have seen me. You should have seen how wisely I proceeded—with what caution—with what foresight—with what dissimulation I went to work!

I have news for the narrator.  Just because a person is careful and exercises caution, doesn't mean he is, or is not, crazy.  I'm sure certified serial killers in real life also think they are not crazy.