"Beyond the Basics""Beyond the Basics" Part II, Section "Mood", Chapter IV: "The Imperative Mood", describes Option 3 for the imperative mood:
Request, a.k.a. Entreaty, Polite Command:
The imperative is often used to express a request. This is normally seen when the speaker is addressing a superior. Imperatives (almost always in the aorist tense) directed toward God in prayers fit this category.