Oneness, Uniqueness of Allah (Tawheed)
Bukhari :: Book 9 :: Volume 93 :: Hadith 492
Narrated Abu Dharr:
When the Prophet went to bed at night, he used to say: "Bismika namutu wa nahya." And when he got up in the morning, he used to say, "Alhamdu lillahi al-ladhi ahyana ba'da ma amatana, wa ilaihi-n-nushur."