It was the practice of the Prophet (peace and blessings of Allah be upon him) to spend the last ten nights of Ramadan in worship.
Narrated 'Aisha (may Allah be pleased with her): "When the last ten nights (of Ramadan) began, Allah's Messenger (peace and blessings of Allah be upon him) would keep awake at night (for prayer and devotion), awaken his family and prepare himself to be more diligent in worship" (Muslim)
In another version of the Hadith, 'Aisha (may Allah be pleased with her) said: "Allah's Messenger (peace and blessings of Allah be upon him) used to strive more (in worship) during the last ten nights of Ramadan than he did during any other time". (Muslim)
Narrated 'Aisha (may Allah be pleased with her): "When the last ten nights (of Ramadan) began, Allah's Messenger (peace and blessings of Allah be upon him) would keep awake at night (for prayer and devotion), awaken his family and prepare himself to be more diligent in worship" (Muslim)
In another version of the Hadith, 'Aisha (may Allah be pleased with her) said: "Allah's Messenger (peace and blessings of Allah be upon him) used to strive more (in worship) during the last ten nights of Ramadan than he did during any other time". (Muslim)