Musnad Ahmad 356:1

Hajjaj narrated to us, he said: Shu'bah narrated to us, from Sa'id al-Jurayri, he said: I heard 'Ubayd ibn al-Qa'qa' narrating to a man from Banu Hanzalah, he said: A man watched the Prophet, may God bless him and grant him peace, while he was praying, and he began to say in his prayer: "O God, forgive me my sin, and expand for me in my home, and bless for me in what You have provided me."