
because he'd SWORN an oath
to your mother.
Game of Thrones Season 8, Episode 2

All of them have SWORN upon their rings
to keep this meeting a secret.
Vikings Season 1, Episode 2

Ser Amory Lorch,
SWORN bannerman to Lord Tywin Lannister.
Game of Thrones Season 2, Episode 3

and SWORN to take revenge against you.
Game of Thrones Season 4, Episode 5

and SWORN brother of the Night's Watch,
ever faithful.
Game of Thrones Season 5, Episode 7