Whenever the Messenger of Allah ﷺ performed the ritual bath, he would pour water over his head three times.
أخبرنا محمد بن عبد الأعلى قال حدثنا خالد عن شعبة عن مخول عن أبي جعفر
كان رسول الله ﷺ إذا اغتسل أفرغ على رأسه ثلاثا
Bukhari transmitted it in the Book of Ghusl, chapter, "Whoever poured water over his head three times," hadith no. 255, from the narration of Shubah. Muslim also transmitted it in the Book of Menstruation, chapter, "The recommendation of pouring water over the head and other parts three times," hadith no. 329, from the narration of Abu Jafar Muhammad bin Ali, with the same chain.