Continuity: When Jack goes into the pub, it is dark outside, but when Ted and Dougal leave the caves, it is daytime, despite both scenes supposedly taking place at the same time.
Great sites
Quotes
Bishop Facks: So, Father. Do you ever have any doubts about the religious life? Is your faith ever tested? Anything you would be worried about? Any doubts you've been having about any aspects of belief? Anything like that?
Father Dougal: Well, you know the way God made us all, right? And he's looking down at us from heaven and everything?
Bishop Facks: Uh-huh.
Father Dougal: And then his son came down and saved everyone and all that?
Bishop Facks: Yes.
Father Dougal: And when we die we're all going to go to heaven?
Bishop Facks: Yes. What about it?
Father Dougal: Well, that's the bit I have trouble with.
Trivia
In the scene where Mrs. Doyle is telling Ted about the profanity in the book, several of the swears were not in the original script but were introduced by Pauline McLynn during filming. You can see Dermot Morgan trying not to laugh at her last line "Ride me sideways", which he hadn't been expecting. See more...
Father Ted (1995) - 1 mistake in "The Mainland"
starring Ardal O'Hanlon, Dermot Morgan, Frank Kelly, Pauline McLynn (add more)
Updates: 
Series 2
The Mainland (season 3, episode 4)
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