Mordecai is one of those characters that truly stands out – he's totally memorable, both to us and to the other characters that meet him. Mordecai was born as Ezra Mordecai Cohen, and he is Mirah's older brother (though we don't find that out until we've known him for quite some time). George Eliot does a pretty good job of helping us to create a mental picture of Mordecai. He can be totally withdrawn and quiet one moment, but, if he gets excited, he'll be right up in your face at the next. He has an intense gaze to match his intense personality; he is skinny and withered-looking, with a gaunt face.
Of course, Mordecai's distinctive physical characteristics help to illustrate another unique – and unfortunate – part of his character: he's dying of tuberculosis. When he fills Daniel in on all the details of his background, Mordecai mentions that he spent a night out in the cold while trying to get back to his mother, who informed him that his evil father stole his younger sister away. Let's suspend our disbelief for a second and pretend that being cold can actually give you tuberculosis. When we think about Mordecai's life and experiences as he relates them to Daniel, we realize that he is a pretty tragic figure. Still, it seems that if there's one person who can withstand serious trials, it's got to be Mordecai. Mordecai is a man of intense spiritual and religious belief, and these beliefs seem to feed him and strengthen him in spite of everything he has to go through. (This might be a good time to mention the significance of Mordecai's name – Mordecai is a major figure in the Book of Esther in the Torah of the Hebrew Bible and in the Old Testament of the Christian Bible.)
One of the most important aspects of Mordecai's spiritual life is the way that he feels compelled to instruct Daniel. Ever since he realized he was dying, Mordecai has been searching for the person to fill his shoes, finishing the work that he started in order to make a better life for the Jewish race. Mordecai searches ceaselessly for a cosmopolitan Jewish man who can inspire awe in other Jews around him and reunite them with their faith. It is Mordecai's sincere hope that one day a Jewish nation might be built that gives the Jews of the world both a religious and national identity (this concept is called Zionism). Mordecai never sees this happen, but he stays alive long enough to learn that Daniel is Jewish and to pass the task on to him.