Sahih Bukhari: Hadith 3556

Fatima complained of the suffering caused to her by the hand mill. Some Captives were brought to the Prophet, she came to him but did not find him at home `Aisha was present there to whom she told (of her desire for a servant). When the Prophet (ﷺ) came, Aisha informed him about Fatima's visit. `Ali added "So the Prophet (ﷺ) came to us, while we had gone to our bed I wanted to get up but the Prophet (ﷺ) said, "Remain at your place". Then he sat down between us till I found the coolness of his feet on my chest. Then he said, "Shall I teach you a thing which is better than what you have asked me? When you go to bed, say, 'Allahu-Akbar' thirty-four times, and 'Subhan Allah thirty-three times, and 'Al hamdu-li l-lah thirty-three times for that is better for you both than a servant."