How does Lee create suspense at the end of this chapter? What does Ewell's comment foreshawdow?

Scout reflects that "in the secret courts of men's hearts," nothing Atticus could have said could have freed Tom. Upon hearing the news, Mr. Ewell is rumored to have said, "one down and about two more to go," and Scout is afraid for Atticus. Jem confidently tells Scout that Mr. Ewell won't really take any action on his threats. This foreshadows Ewell's cowardly attack on the children later.