«والنهي لغة: قول القائل لغيره على سبيل الاستعلاء: لا تفعل»
Linguistically, prohibition is an authoritative statement to another: “Do not do it.”
«واصطلاحاً: إلزام ترك الفعل على الغير»
Technically, it obliges another to refrain from an action.
«ولا تقربوا الزنا»
Do not approach unlawful sexual intercourse.
Commands require performance; prohibitions require refraining. Both are normative forms of address, but their immediate demands are opposite.