Narrated `Abdullah: I never saw the Prophet offering any prayer not at its stated time except two; he prayed the Maghrib and the `Isha' together and he offered the morning prayer before its usual time.
Hadith ReferenceSahih Bukhari / The Book of Hajj / Hadith: 1682
Hadith Gradingمحدثین:أحاديث صحيح البخاريّ كلّها صحيحة