Al-Adab Al-Mufrad, Book 50, Hadith 1218 (In-Book) ⓘ

Rabi'a ibn Ka'b related, "I used to spend the night at the door of the Prophet, may Allah bless him and grant him peace, and I would give him his wudu' water." He said, "After a long period of the night had passed, I heard him say, 'Allah hears whoever praises Him,' and I heard him say after a long period of the night had passed, 'Praise be to Allah, Lord of the Worlds.'"

حَدَّثَنَا مُعَاذُ بْنُ فَضَالَةَ، قَالَ‏:‏ حَدَّثَنَا هِشَامٌ الدَّسْتُوَائِيُّ، عَنْ يَحْيَى هُوَ ابْنُ أَبِي كَثِيرٍ، عَنْ أَبِي سَلَمَةَ قَالَ‏:‏ حَدَّثَنِي رَبِيعَةُ بْنُ كَعْبٍ قَالَ‏:‏ كُنْتُ أَبِيتُ عِنْدَ بَابِ النَّبِيِّ صلى الله عليه وسلم فَأُعْطِيهِ وَضُوءَهُ، قَالَ‏:‏ فَأَسْمَعُهُ الْهَوِيَّ مِنَ اللَّيْلِ يَقُولُ‏:‏ سَمِعَ اللَّهُ لِمَنْ حَمِدَهُ، وَأَسْمَعُهُ الْهَوِيَّ مِنَ اللَّيْلِ يَقُولُ‏:‏ الْحَمْدُ لِلَّهِ رَبِّ الْعَالَمِينَ‏.‏