Candida R. Moss holds a chair in theology at the University of Birmingham and is co-author of "Reconceiving Infertility: Biblical Perspectives on Childlessness and Procreation" (Princeton University Press, 2015). The opinions expressed in this commentary are hers.

(CNN) In an unprecedented move, Pope Francis married a Chilean flight-attendant couple midflight from Santiago to Iquique on Thursday morning. The couple, who are legally married, had planned to wed almost eight years ago but were forced to postpone their plans when an enormous earthquake destroyed the church where they were to hold their service. They ended up with a civil service.

Candida Moss

Upon learning they had not been married by the church, Francis offered to marry them on the plane. Francis blessed their rings and a cardinal drafted a handwritten wedding certificate.

It's a heartwarming story and another example of Francis spontaneously veering off-script to promote the church, its teachings, and his own central teaching of love. (Recently, Francis told mothers they should feel free to breastfeed in the Sistine Chapel, adding that it is the "language of love.")

This impromptu wedding may ruffle some feathers within the church. Critics might note that Francis had no way to know whether the couple -- Paula Podest, 39, and Carlos Ciufardi, 41-- had completed the Pre-Cana marital instruction generally required of those who would marry in the Roman Catholic Church (or even that the two had been baptized and were actually Catholic). Others will object that the Code of Canon Law specifies that couples should marry in a proper church building.

Of course, the Pope could grant a special dispensation, but his actions are sure to displease those who already think he might not be taking marriage seriously enough.

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