Let it be known, Jacob Marley is dead. The narrator assures us that this is the case for the past seven years: Marley is indeed dead. And this must be clear, perfectly clear, if the rest of the tale we are about to hear is true. And as important, Scrooge, our soon to meet protagonist knows this. See, Marley and Scrooge, Scrooge and Marley, were business partners. Scrooge saw to his burial, and was his executor. Two of a kind they were, cold and hard in life. Men who care about money, and money alone.
Secondly, today is Christmas Eve. A time for most people, that brings out their better angels and love and care for all humanity, including the downtrodden. This was not true for Marley when he lived, and it is not true for Scrooge in his life, and especially not today.