I caught Four Weddings and a Funeral the other day. I hadn't seen it in years and I had forgotten how funny it was. This clip features Mr. Bean officiating at one of the four weddings in the film and he makes a bunch of mistakes because this is his first wedding.
I thought the couples (even though it is scripted) handled all of the Vicar's mistakes with grace and set a good example for brides and grooms-to-be. My sister's officiant actually made a mistake with our grandmother's name during the ceremony—her name is Leonora and he called her Leonard—and besides a few chuckles from the bride and groom and a few guests we just let it slide.
If your officiant makes similar mistakes at your ceremony I suggest you follow Lydia and Bernard's example and make the corrections when necessary, but do not embarrass the officiant or draw unnecessary attention to it. Many of your guests may not even notice the error in the first place. —Anne Chertoff