The premiere of The Young Pope is alternately surprising and expected. The title tells it all: this pope is young. He is also quite perturbed by waking up in his new accommodations, and after a lengthy introduction to the pope's morning routine, there's a shocking moment where Pope Pius declares that he supports abortion — and non-procreative sex, LGBT rights, and allowing women to be priests. However, those proclamations all turn out to be a part of what seems, as of the first episode, to be nothing more than Pope Pius XIII's dream sequences, which play "gotcha" with his progressivism and his aggressiveness.
In real life, Pius (real name: Lenny) is outrageously rude and offensive, demanding that his personal chef, a delightfully charming nun, stop trying to be "friendly" because he hates friendship and would prefer deference. (He only drinks Cherry Coke Zero for breakfast.) A controversial decision he makes early on is to hire Sister Mary as his personal secretary, an important position that in this fictional version of the Catholic Church, seems to have never been held by a woman before. However, that isn't accurate to the real Vatican, as current Pope Francis had a female secretary, who sadly died in early 2016.
But the meaning behind that decision on the show is twofold. First of all, it establishes that yes, Pius will be changing things in a way that will make the establishment horrified. Cardinal Voiello practically has a spit take at the news, because it puts a wrench in his plans to spy on, usurp, and unseat Pius, presumably in order to take his place.
But it also suggests that while Pius' initial speech might not have been real, he does intend to genuinely change and shake up the Church. This was a handy way for The Young Pope to show non-Catholic viewers that nuns, despite being devoted service members, find it much more difficult to advance to positions of leadership within the church. And that opening scene, where Voiello tells Piuus that he's no longer the pope, could be more than just a dream. It could be foreshadowing that Pius' love of change could ultimately bring his dreams of radically altering the Church to an early end.