Wolverine converted to Catholicism.
In X-Men: The Animated Series (specifically Season 4 episode 8 titled "Nightcrawler"), Logan is portrayed as a bitter, violent man deeply angry at God.
He meets Nightcrawler, as a devout Catholic monk who has been hunted and hated by the world, yet feels at peace. Kurt’s pure faith completely shatters Logan's cynicism.
In the final scene of the episode, Wolverine is shown kneeling alone at the altar of a French monastery, physically crossing himself and reading the Bible.
Having the humility to kneel is the only thing that can actually heal a broken soul.