The Prophet ﷺ came to the mosque of Banu AbdulAshhal. He prayed the sunset prayer there. When they finished the prayer, he saw them praying the supererogatory prayer after it. He said: This is the prayer to be offered in the houses.
أَنَّ النَّبِيَّ ﷺ أَتَى مَسْجِدَ بَنِي عَبْدِ الأَشْهَلِ فَصَلَّى فِيهِ الْمَغْرِبَ فَلَمَّا قَضَوْا صَلاَتَهُمْ رَآهُمْ يُسَبِّحُونَ بَعْدَهَا فَقَالَ هَذِهِ صَلاَةُ الْبُيُوتِ