Itikaf (Praying in the last ten nights of Ramadan)
Al-Bukhari and Muslim record from ‘Aishah that during the last ten days of Ramadan, the Messenger of Allah would wake his wives up during the night and then remain apart from them (that is, being busy in acts of worship). A narration in Muslim states: “He would strive [to do acts of worship] during the last ten days of Ramadan more than he would at any other time.”
Aisha reported that With the start of the last ten days of Ramadan, the Prophet used to tighten his waist belt (i.e. work hard) and used to pray all the night, and used to keep his family awake for the prayers. [Bukhari]