Place of wand to hands
- Ron: "An Unbreakable Vow? Nah, he can't have...Are you sure?"
- Harry: "Yes, I'm sure. Why, what does that mean?"
- Ron: "Well, you can't break an Unbreakable Vow...."
- Harry: "I'd worked that much out for myself, funnily enough. What happens if you break it, then?"
- Ron: "You die."
- — Ron and Harry discuss the spell.[src]
Casting and effects
- "A thin tongue of brilliant flame issued from the wand and wound its way around their hands like a red-hot wire."
- —The light of the spell after the first clause.[src]
The Vow is cast by having two wizards kneeling opposite each other and clasping right hands. A third wizard must hold their wand, standing quite close to the pair holding hands, and place the tip of their wand onto the linked hands, as Bonder. Then, the first will ask a certain number of vows of the other, with the second accepting those terms; it is unknown what happens if he or she declines. Each time a term is accepted a thin stream of fire will be emitted from the Bonder's wand, weaving around the hands of the pair taking the vows.
- "Fred and George tried to get me to make one when I was about five. I nearly did too, I was holding hands with Fred and everything when Dad found us. He went mental, only time I've ever seen Dad as angry as Mum. Fred reckons his left buttock has never been the same since."
- —Ron describing his brothers' attempt to make him use the spell.[src]
In either 1985 or 1986, Fred and George Weasley attempted to convince their then five-year-old brother Ron to make an Unbreakable Vow with them. They were in fact poised to do so, with their wands out, holding hands and ready to cast the spell when their father discovered them. It was described as the only time he was as angry as his wife, and it is said that he did something which left Fred's left buttock never feeling the same way again; however, luckily their brother Ron was left unhurt, although he remembered the incident at least eleven years later.
- Snape: "You will need your wand, Bellatrix, and you will need to move a little closer."
- Narcissa: "Will you, Severus, watch over my son, Draco, as he attempts to fulfill the Dark Lord's wishes?"
- Snape: "I will"
- Narcissa: "And will you, to the best of your ability, protect him from harm?"
- Snape: "I will"
- Narcissa: "And should it prove necessary...if it seems Draco will fail...will you carry out the deed that the Dark Lord has ordered Draco to perform?"
- Snape: "I will"
- — Severus and Narcissa's vow[src]
Nearly ten years later, Professor Severus Snape made an Unbreakable Vow with Narcissa Malfoy, the wife of a death eater. Their Bonder was Bellatrix Lestrange, Narcissa's sister and a Death Eater. He promised to protect Draco Malfoy from harm and guide him whilst he attempted to perform the task the Dark Lord had asked him to do: to kill Albus Dumbledore.
Behind the scenes
- It is unknown if this spell has an incantation; although the Bonder has to hold their wand to the peoples' hands, it would seem at first as though the vows themselves were the incantation. However, no spell whatsoever in the Harry Potter universe has not had an incantation, and hence it is likely it was merely cast non-verbally.
- Harry Potter and the Half-Blood Prince
- Harry Potter and the Half-Blood Prince (film)
- Harry Potter and the Half-Blood Prince (video game)
- LEGO Harry Potter: Years 5-7
Notes and references
Intersting Fact: L'Estrange v Graucob is an English case in contract law setting the general rule that persons are bound by their signature regardless of whether they have read the agreement. E.g. A is bound to any contract it signs whether or not A has read that contract. L'Estrange v F Graucob Ltd  2 KB 394.