the letter
Strict adherence to or interpretation of something, such as a law or rule, exactly as it is written or instructed I know he's the mayor's cousin, but we need to follow the letter of the law so as to not get accused of giving him preferential treatment. You have to complete every step of the instructions to the letter for this program to work.
Farlex Dictionary of Idioms. © 2024 Farlex, Inc, all rights reserved.