Here is something interesting I found on Wikipedia (yes I know!):
As Hugo set to work on the novel in 1848 after a long interruption, his anti-clerical son Charles objected to presenting Myriel as "a prototype of perfection and intelligence", suggesting instead someone from "a liberal, modern profession, like a doctor". The novelist replied:
I cannot put the future into the past. My novel takes place in 1815. For the rest, this Catholic priest, this pure and lofty figure of true priesthood, offers the most savage satire on the priesthood today.