Sayyiduna Abu Hurairah (may Allah be pleased with him) narrated that on the day of the conquest of Makkah, the Messenger of Allah (peace and blessings be upon him) stood up and said: "Allah Almighty prevented the elephants from entering Makkah, but He granted victory over it to His Messenger and the Muslims. Behold! Makkah was not made lawful for anyone before me (that is, fighting in Makkah), nor will it be made lawful for anyone after me. Listen! From this moment, Makkah is again sacred (forbidden for fighting); its thorns are not to be cut, its trees are not to be cut, and nothing dropped in it is to be picked up except by one who announces it, that is, the one who intends to return it to its owner—only he may pick up something found."
Hadith Referenceسنن دارمي / من كتاب البيوع / 2636
Hadith Gradingتحقیق (حسین سلیم أسد الدارانی):إسناده صحيح والحديث متفق عليه، [مكتبه الشامله نمبر: 2642]