والمعتزلة اعتقدوا أن الأمر يستلزم الإرادة، والنهي عدم الإرادة
The Muʿtazilah held that command entails will, and prohibition entails the absence of will.
But command and prohibition concern normative obligation, whereas creative volition concerns the occurrence of events. Someone may be commanded to speak truthfully and choose to lie instead; a forbidden act may still happen. This does not reduce the binding force or truth of the divine command.
Thus “this is commanded” does not imply that every addressee will necessarily obey, and “this is forbidden” does not mean that no one will ever perform it. The distinction answers a central difficulty in the debate.