[Machine] I used to sleep in the Prophet's room ﷺ and I would hear him when he would wake up at night to pray, saying: "Alhamdulillah Rabbil 'Alameen" quietly, then he would say: "Subhanallah Rabbi al-'Azeem wa bihamdih" quietly. I asked, "What is quietly?" He said, "He makes supplication for a period of time."
كُنْتُ أَنَامُ فِي حُجْرَةِ النَّبِيِّ ﷺ وَكُنْتُ أَسْمَعْهُ إِذَا قَامَ مِنَ اللَّيْلِ يُصَلِّي يَقُولُ «الْحَمْدُ لِلَّهِ رَبِّ الْعَالَمِينَ» الْهَوِيَّ ثُمَّ يَقُولُ «سُبْحَانَ رَبِّي الْعَظِيمِ وَبِحَمْدِهِ» الْهَوِيَ قُلْتُ مَا الْهَوِيُّ فَقَالَ «يَدْعُو سَاعَةً»