Musnad Ahmad 429:15

Aswad ibn Amir narrated to us, he said: Hammad ibn Salamah narrated to us, from Amr ibn Dinar, from Nafi ibn Jubayr, from his father, from the Prophet, peace and blessings of Allah be upon him, who said: "Allah, the Almighty and Majestic, descends every night to the lowest heaven, and He says: 'Is there any asker, so that I may give him? Is there any seeker of forgiveness, so that I may forgive him?' until the dawn breaks."