وَصِيغَتُهُ تُسْتَعْمَلُ فِي مَعَانٍ كَثِيرَةٍ
Its form is used for numerous meanings.
An imperative form has a wide pragmatic range: direct command, permission, threat, subjugation, humiliation, wishing, supplication and entreaty can all be expressed through it. The variety does not prove that all uses are equally primary lexical meanings.
The argument from tabādur (the immediate meaning that comes to mind without special evidence) supports the primary sense of directing an action. By contrast, when fulfillment is impossible or the situation signals contempt, a rhetorical rather than a literal command is indicated.