[Machine] The Prophet ﷺ used to pray at Al-Hijr or Al-Hajirah, and it was the most difficult prayer for his companions. Then the verse {Maintain with care the [obligatory] prayers and [in particular] the middle prayer and stand before Allah, devoutly obedient.} was revealed. He said, "Because before it there were two prayers and after it there were two prayers."
أَنَّ النَّبِيَّ ﷺ كَانَ يُصَلِّي بِالْهَجِيرِ أَوْ قَالَ بِالْهَاجِرَةِ وَكَانَتْ أَثْقَلَ الصَّلَاةِ عَلَى أَصْحَابِهِ فَنَزَلَتْ {حَافِظُوا عَلَى الصَّلَوَاتِ وَالصَّلَاةِ الْوُسْطَى وَقُومُوا لِلَّهِ قَانِتِينَ} قَالَ «لِأَنَّ قَبْلَهَا صَلَاتَيْنِ وَبَعْدَهَا صَلَاتَيْنِ»