HBO’s The Young Pope is much more thoughtful (and much weirder) than the rampant memes it’s spawned would have you believe — and this only becomes more evident as the series continues. The actions of Pope Pius XIII (Jude Law), a.k.a. Lenny Belardo, are unpredictable because the forces driving him are complicated, and the show reveals the specifics of these forces very slowly.
But the main cause of Lenny’s erratic behavior and yen for papal revolution boils down to something simple: a sense of abandonment. Not just abandonment by his parents, who dropped him at the gates of an orphanage when he was a boy, but, more fundamentally, abandonment by God.