The marriage in the sky, a papal first, was the type of spontaneous gesture that has made Francis an endearing global figure. It played out like a script from the old TV series The Love Boat. The only way it would have melted more hearts was if it occurred on Valentine’s day.

On the ground, however, the wedding is bound to cause some turbulence for parish priests who, rather than follow their heart, must let instructions from their bishop and the norms of the Church dictate how they conduct the Sacrament of Matrimony. Church law is explicit on weddings, as priests constantly explain to engaged couples who want to be married at sunset on the beach or in a rose garden or at the bowling alley where they first locked eyes. Catholic weddings, priests dutifully instruct, occur in a Catholic church usually during Mass and following a period of preparation.

Those conversations, however, are today more challenging for priests after Pope Francis declared a Chilean couple man and wife in a cramped row of an Airbus 321. If the Pope can wing it for a couple he barely knows, then other engaged couples may understandably wonder why their wedding must obey all the rules, and why their pastor can’t follow the Pope’s example and make an exception for them?

According to the Chilean couple, the Pope encouraged their marriage because he believed it would inspire other civilly married couples to be married in the Church.

“This is the sacrament the world needs,” the groom quoted Pope Francis. “Hopefully, this will motivate couples around the world to get married.”

Encouraging Catholics towards sacramental marriage is, of course, a worthy objective. But it’s fair to ask how weddings on the fly further that goal. In his 2016 papal document Amoris Laetitia, Pope Francis cautioned couples against getting “wrapped up” in wedding hoopla and losing sight of matrimony’s sacramental essence and the “profound significance” of the liturgical rite of marriage. To accomplish that, he said, requires thorough marriage preparation.

It is during months of preparation that, among many things, couples are taught the sacramental foundation of marriage and why the Sacrament of Matrimony is conducted during a Mass in a church; why they must be in good standing with the Church; why their marriage is irrevocable; why they must show there are no impediments to their marriage; why every aspect of the marriage, from the liturgy to the reception, should respect the sacredness of the sacrament.

So by all means toast the Chilean love birds, but no one should regard this unorthodox ceremony as a Church prototype ready for takeoff.