Why did the spirit visit Scrooge what was his reaction?

There were four in total. The very first was the ghost of his dead business partner Jacob Marley. Jacob is allowed back to the realm of the living to warn Scrooge that his miserly nasty ways will see him die soon and his afterlife would be spent like Marley's in everlasting torment. To that end Marley foretells of 3 more visitations all of whom would seek to help Scrooge make the changes that would see his life and after life change