Sunan an-Nasa'i 2195

Urwah bin Az-Zubair narrated that 'Aishah told him:"The Messenger of Allah went out in the middle of the night and prayed in the Masjid," and he quoted the same Hadith, in which he said: "nd he encouraged them to pray Qiyam in Ramadan, without insisting on that, and he said: 'Whoever spends the nights of Ramadan in prayer (Qiyam) out of faith and in the hope of reward, he will be forgiven his previous sins