Jabir bin Yazid bin Al-Aswad Al Amir told us that his father said:
I attended Fajr prayer with the Messenger of Allah (ﷺ)in Masjid Al Khaif. When he finished praying, he saw two men at the back of the people who had not prayed with him. He said: 'Bring them here.' So they were brought to him, trembling. He said: 'What kept you from praying with us? They said: '0 Messenger of Allah (ﷺ) we has already prayed in our lodgings.' He said: 'Do not do that. If you have already prayed in your lodgings, then you come to a Masjid in which there is a congregation, then pray with them, and it will be a voluntary prayer for you. '