
He swore an OATH, Cat.
Game of Thrones Season 1, Episode 1

I'm a Kingsguard, forbidden by
OATH to carry on the family line.
Game of Thrones Season 4, Episode 6

But still, an OATH is an OATH.
Game of Thrones Season 7, Episode 3

I swore an OATH to House Tyrell.
Game of Thrones Season 7, Episode 2

Any OATH that you swear
on these rings must be honored and kept.
Vikings Season 1, Episode 1