The sacrament of marriage requires human witnesses, but do you need some people sitting in the aisles to witness it or could it theoretically just be the couple and a priest?
I am open to correction, but in theory you don’t even need a priest.
If the circumstances are extreme you could take the vows and intend to get the witnesses and priests later and it should be valid.
For example if you were stuck on a desert island. Or if Catholics were being persecuted and marriage was impossible.
When my great-grandparents were married, they were Catholics living in the former USSR under Stalin. Catholicism was illegal. They were married secretly in the middle of the night. The only people in the church were the two of them, the priest, and another man who was the witness (only one witness was required at the time).
It’s not exactly the same thing because there were witnesses but Pope Francis presided of a marriage on his plane. Maybe not the wisest thing to do but then again he is the Pope.
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