Sunan Abi Dawud
Hadith #426
Narrated Umm Farwah: The Messenger of Allah (ﷺ) was asked: Which of the actions is best? He replied: Observing prayer early in its period. Al-Khuza'i narrated in his version from his aunt named Umm Farwah who took the oath of allegiance to the Prophet (ﷺ): He was questioned