They see St. Peter up in heaven, and ask him if he can marry them. He says "nobody ever asked me that up here in heaven before. I'll have to check with God almighty."
So he brings them to see God, and God says, "come back and see me in 5 years, and if you still want to, we'll perform the ceremony."
5 years go by, and they still want to, so they go see God again.
"I'm sorry, but we still can't do it. Come back in another 5 years if you still wish to get married, and I PROMISE that we'll perform the ceremony."
5 more years go by, they still want to, so they visit God a third time. He says "ok, we'll do it". They have a big lavish wedding up there in heaven.
The marriage is a disaster. They come back to God one month after the wedding. "God, it's a disaster. We want a divorce. Can you help us?"
A divorce?! It took 10 years to find a priest. How long do you think it'll take to find a lawyer?!