Musnad Ahmad 31:578

Mu'awiyah ibn 'Amr narrated to us, Za'idah narrated to us, from al-A'mash, from Abu Sufyan, from Jabir, from Abu Sa'id, from the Prophet, peace and blessings of Allah be upon him, who said: "When one of you completes his prayer in the mosque, let him assign a portion of his prayer to his house, for indeed Allah will place goodness in his house from his prayer."