Passive versions of active expressions turn the subject into an object.
I ate the candy.
The candy was eaten by me.
Imperatives often have an implied subject of "you":
(You) do not open the door.
You do not open the door.
The door is not opened by you.
However the door is not opened by you loses its "imperativeness" and sounds like you are narrating someone's actions - which further sounds odd because it appears you're trying to read someone's mind. So, options to put the "imperativeness" back include
- Using let in the sentence - let is a polite way to indicate an imperative. Let requires a subjunctive. This sounds mythical and archaic, don't use it in real conversation.
Let that the door not be opened by you.
- Better - use a modal - modals are often "misused" to imply imperatives. Use should to be polite, may to be condescending/come off as talking to a child, will to be really demanding, or shall to be snobby and demanding.
The door should not be opened by you.