Nubayt bin Sharit (may Allah be pleased with him) says: I was riding behind my father on the back of the mount. The Prophet (peace and blessings be upon him) was delivering a sermon near the Jamrah, and he (peace and blessings be upon him) said: 'Al-hamdu lillahi nahmaduhu wa nasta'inuhu wa nastaghfiruhu, wa ashhadu an la ilaha illallahu, wa anna Muhammadan 'abduhu wa rasuluhu' "All praise is for Allah; we praise Him, we seek His help and we seek His forgiveness, and I bear witness that there is no god but Allah and that Muhammad (peace and blessings be upon him) is the servant and Messenger of Allah."
"I enjoin upon you the fear of Allah. Which day is the most sacred?" The Companions (may Allah be pleased with them) replied: This very day. He (peace and blessings be upon him) asked: "Which month is the most sacred?" The Companions (may Allah be pleased with them) replied: This very month is the most sacred. He (peace and blessings be upon him) asked: "Which city is the most sacred?" The Companions (may Allah be pleased with them) replied: This very city. He (peace and blessings be upon him) said: "Your blood and your wealth are sacred to one another among you, just as the sanctity of this day of yours, this month and this city."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الجمعة / 5806