A Bedouin entered the masjid and prayed two rak'ahs, then he said: "O Allah, have mercy on me and on Muhammad and do not have mercy on anyone else." The Messenger of Allah ﷺ said: "You have limited something vast."

أَنَّ أَعْرَابِيًّا دَخَلَ الْمَسْجِدَ فَصَلَّى رَكْعَتَيْنِ ثُمَّ قَالَ اللَّهُمَّ ارْحَمْنِي وَمُحَمَّدًا وَلاَ تَرْحَمْ مَعَنَا أَحَدًا فَقَالَ رَسُولُ اللَّهِ ﷺ لَقَدْ تَحَجَّرْتَ وَاسِعًا