As the high priestess of the god Karnak, to have done less would have been committing sacrilege.
5 seconds sound clip from the The Mummy (1959) movie soundboard.
You can hear this line at 00:37:33.360 in the Blu-ray version of the movie.
Quote context
[...]
- Maidens bearing the Ushabti, symbols of mythical power and significance.
- The royal mummy itself, the mortal remains of the Princess Ananka.
- As the high priestess of the god Karnak, to have done less would have been committing sacrilege.
- And behind him came the casket containing the heart of the princess.
- Much blood was to flow during the succeeding days.
[...]