Musnad Ahmad 30:1853

'Affan narrated to us, he said: Abu 'Awanah narrated to us, from Abu Ishaq, from al-Agharr Abu Muslim, he said: I bear witness regarding Abu Hurayrah and Abu Sa'id that they both bore witness regarding the Messenger of Allah, may Allah bless him and grant him peace, that he said: "Indeed, Allah grants respite until the first third of the night passes, then He descends and says: 'Is there any supplicant who will be answered? Is there any seeker of forgiveness who will be forgiven?'" And 'Affan said: "Abu 'Awanah had narrated to us hadiths from Abu Ishaq, then it reached me later that he said: 'I heard them from Isra'il, and I reckon this hadith is among them.'"