Who said "A man must do his duty, even unto death."?

This quote is attributed to Melisandre.

A man must do his duty, even unto death. - Melisandre

"A man must do his duty, even unto death."

Melisandre Courage

"The night is dark and full of terrors."

"There is no night and day in the void, no time, only darkness and cold."

"I have seen the future in the flames."

"The Lord of Light demands blood."

"Never let fear stop you from chasing your dreams."

"Courage is being afraid but doing it anyway."

"Sometimes you gotta do what you gotta do."

"Sometimes you have to be the monster to stop the monsters."