[Machine] He heard the Prophet ﷺ say, "Allah does not look at the prayer of a servant who does not straighten his backbone between the bowing and prostration."
أَنَّهُ سَمِعَ النَّبِيَّ ﷺ يَقُولُ لَا يَنْظُرُ اللهُ إِلَى صَلَاةِ عَبْدٍ لَا يُقِيمُ صُلْبَهُ بَيْنَ رُكُوعِهِ وَسُجُودِهِ