It’s 10am on Sunday, and people are already starting to filter through the doors of Harbour Church. Sun streams through the windows – there’s an air of anticipation as congregation members greet each other and catch up on the week just gone. Soon, the room is filling up, the sound of gentle chatter swelling as the throng grows and people take their seats. The five-piece worship band strikes up; the crowd gets to its feet; the air vibrates as more than a hundred voices sing praises to God.

Is Christianity back? Across several countries, the last few months have seen numerous anecdotal reports of a resurgence of Christian observance. Many British clerics are noting strong attendances at Lenten and Easter services. Similar reports are emerging in the USA, where younger people make up much of the increase. Meanwhile, France has had a 50% rise in adult baptisms, and survey data suggests a fourfold increase in Catholic observance among 18 to 24-year-olds in Britain.

Sydney Johnston grew up in a nondenominational Christian household — but now the Upper West Side millennial is a devout Catholic.

“There’s just something so beautiful and transcendent about the rituals and the ancient history in the Catholic Mass that’s been preserved,” Johnston, 30, told The Post. “The church really communicates a degree of reverence that I didn’t find in the more liberal, laissez-faire approach of nondenominational churches.”

Predict who the next pope will be at your peril.

An old Italian saying warns against putting faith, or money, in any presumed front-runner ahead of the conclave, the closed-door gathering of cardinals that picks the pontiff. It cautions: "He who enters a conclave as a pope, leaves it as a cardinal".

But here are some cardinals who are being talked about as "papabili" to succeed Pope Francis, whose death at the age of 88 was announced by the Vatican on Monday. They are listed in alphabetical order...

Pope Francis’ famous exhortation to Catholic youth just months after being elected the 266th pope of the Catholic Church in March 2013 was “Hagan lio!” — “make a mess!” Twelve years later, upon his death Easter Monday morning at age 88, it’s fair to say that Francis took his own advice, making a mess of his pontificate and leaving the Catholic Church in a state of confusion and disarray.