[Machine] The Prophet ﷺ used to perform them (two units) after Witr prayer while sitting down, reciting in them when the earth would shake, and say: "O disbelievers!"
أَنَّ النَّبِيَّ ﷺ كَانَ يُصَلِّيهِمَا بَعْدَ الْوِتْرِ وَهُوَجَالِسٌ يَقْرَأُ فِيهِمَا إِذَا زُلْزِلَتِ الْأَرْضُ وَقُلْ يَا أَيُّهَا الْكَافِرُونَ