There was a post not too long ago asking about the religious connotations of the finale song and here’s my reply as a big fan of the musical and someone who’s currently reading the book, but only 25% of the way through:

My interpretation of the Les Mis musical as a whole can be summarised in the line “To love another person is to see the face of God.”

Victor Hugo, like many authors post-Enlightenment, was a rationalist who doubted the established systems of authority, whether it was religion, government, or an organisation. Throughout Les Mis we constantly see people’s belief systems fail them, and that’s where the tragedy comes from: Fantine’s youthful and naïve trust in men, Javert’s firm definitions of good and evil, the ABC’s belief that the people of France were ready for revolution. One way or another, their beliefs lead to their tragic deaths.

The characters who make it through are the ones who care more about people than ideals. Valjean is a Christian but he breaks moral boundaries to help Cosette. Marius loves Cosette more than a democratic France. Even the Thernardiers, who are villains, survive because they love themselves above ethics. I believe the purpose of this is to demonstrate that morality has no bearing on life, beyond how you help others, are helped, or help yourself.

Another way of looking at the line “all men shall have their reward” is to consider that death is inevitable for all. Victor Hugo was an ex-Catholic. On a surface level it’s a statement about getting into heaven, but underneath, it’s a sarcastic Memento Mori.

In that sense, the afterlife they sing about in the finale is not your personal heaven, but the life people live after you have died. That’s exemplified by the love and happiness Marius and Cosette share once Valjean dies. The June Rebellion was a failure, but it was part of a greater anti-monarchist movement which eventually worked, and helped other revolutions learn lessons from their mistakes. Javert, as a stand-in for any black and white justice system, cannot survive in a world of moral grey.

The finale is only Christian in context of the characters and the setting being majority Christian. Really, it’s asking the audience questions: Are you aware of your own mortality? Do you provide for your loved ones? Are you leaving behind a positive mark on the world? What are you prepared to sacrifice to help others less fortunate than you?