To live with rigor
Why bother setting principles so high that you can’t possibly live up to them?
The principles should be solid, rigorous and lofty, because the person following them is flawed and imperfect. If you’re going to fail to live up to principles, they may as well be great ones. And if you partly live up to them, they will raise you up.
A flawed human being who aspires to be more is a step ahead of a flawed human being who never tries.