"Merlin's beard" is a common wizarding expression used to show surprise. There are several coarser variants, including "Merlin's pants," "Merlin's most baggy Y-fronts," and "Merlin's saggy left —" (Arthur Weasley interrupted Ronald Weasley before he could complete this last expression). This might be more insulting than others because of Molly Weasley's reaction.
Amos Diggory, like many others, used this expression when he met Harry Potter. Professor Horace Slughorn used this expression when Professor Dumbledore stuck his wand into Horace, who was transfigured into an armchair in 1996.
Behind the scenes
- In the film adaptation of Harry Potter and the Half-Blood Prince, Professor Slughorn uses this expression very often.
- Harry Potter and the Goblet of Fire (film) (First mentioned)
- Harry Potter and the Order of the Phoenix (film) (Mentioned only)
- Harry Potter and the Half-Blood Prince (Mentioned only)
- Harry Potter and the Half-Blood Prince (film) (Mentioned only)
- Harry Potter and the Deathly Hallows (Not only Merlin's beard) (Mentioned only)
- Famous Wizard Card (First appearance)