I can't write the essay for you, but I can help with key points.
You're writing a five paragraph essay, first, is it informative, opinion, or any other. Think like the author, why would the author include this quote, and is it a direct quote from Martin Luther King Jr?
There's mention of a novel, so you'll have to skim the first chapters a few times to try and find this quote. Be sure to look over any notes about characters you took throughout the novel.
"I believe that unarmed truth and unconditional love will have the final word in reality." You need to compare the meaning of this quote to the one who said it, does the one who said this quote actually believe it?
I hoped this helped a bit. Sorry!