In A Christmas Carol the Ghost of Christmas Past's job is to show Scrooge that past Christmases that he enjoyed. The goal is to provide Scrooge with a remembering of how Christmas used to make him feel. He also shows Scrooge how despite the joy of the season, as time wore on that he began to view it with less joy, turning away from anything that would have brought him joy or comfort (like Belle) and embraced his only love....greed and money. He's showing him the consequences of his choices. And, it is interesting to note that during this reliving of the past, he would make different choices. He 'wants' his former self to go after Belle, to stop her. He knows now what he threw away, and he's beginning to have regrets.