Scrooge's transformation is partly motivated by selfishness, as the visions of the spirits show him his own death and he begs to "sponge away the writing on this stone"
Show he wasn't always mean, his sad ending relationships with Belle show he is capable of love and kindness, and the change in his father foreshadows Scrooge's own redemption
Redemption doesn't rely on religious beliefs, instead it is redeemed by his behaviour towards others, which Dickens thought Christianity should be about
Marley is portrayed to be similar to Scrooge, and his "chance at hope" that Scrooge will save himself shows Scrooge can now help himself change, just like Marley
The Ghost of Christmas Present: '"I see a vacant seat," replied the Ghost, "in the poor chimney corner, and a crutch without an owner, carefully preserved. If these shadows remain unaltered by the Future, the child will die."'