Musnad Ahmad 31:762

'Ali ibn Bahr narrated to us, 'Isa ibn Yunus narrated to us, from al-A'mash, from Abu Salih, from Abu Sa'id al-Khudri, who said: The Messenger of Allah (peace and blessings of Allah be upon him) said during the Farewell Pilgrimage: "Behold, the most sacred of days is this day of yours, and the most sacred of months is this month of yours, and the most sacred of lands is this land of yours. Behold, your wealth and your blood are sacred to you, like the sacredness of this day of yours, in this land of yours, in this month of yours. Behold, have I conveyed?" They said: "Yes." He said: "O Allah, bear witness."