Al-Adab al-Mufrad, hadith 12

حَدَّثَنَا عَبْدُ اللهِ بْنُ صَالِحٍ قَالَ‏:‏ حَدَّثَنِي اللَّيْثُ قَالَ‏:‏ حَدَّثَنِي خَالِدُ بْنُ يَزِيدَ، عَنْ سَعِيدِ بْنِ أَبِي هِلاَلٍ، عَنْ أَبِي حَازِمٍ، عَنْ أَبِي مُرَّةَ مَوْلَى عَقِيلٍ، أَنَّ أَبَا هُرَيْرَةَ كَانَ يَسْتَخْلِفُهُ مَرْوَانُ، وَكَانَ يَكُونُ بِذِي الْحُلَيْفَةِ، فَكَانَتْ أُمُّهُ فِي بَيْتٍ وَهُوَ فِي آخَرَ‏.‏ قَالَ‏:‏ فَإِذَا أَرَادَ أَنْ يَخْرُجَ وَقَفَ عَلَى بَابِهَا فَقَالَ‏:‏ السَّلاَمُ عَلَيْكِ يَا أُمَّتَاهُ وَرَحْمَةُ اللهِ وَبَرَكَاتُهُ، فَتَقُولُ‏:‏ وَعَلَيْكَ السَّلاَمُ يَا بُنَيَّ وَرَحْمَةُ اللهِ وَبَرَكَاتُهُ، فَيَقُولُ‏:‏ رَحِمَكِ اللَّهُ كَمَا رَبَّيْتِنِي صَغِيرًا، فَتَقُولُ‏:‏ رَحِمَكَ اللَّهُ كَمَا بَرَرْتَنِي كَبِيرًا، ثُمَّ إِذَا أَرَادَ أَنْ يَدْخُلَ صَنَعَ مِثْلَهُ‏.‏

Marwan used to make Abu Hurayra his agent and he used to be located in Dhu'l-Hulayfa. His mother was in one house and he was in another. When he wanted to go out, he would stop at her door and say, "Peace be upon you, mother, and the mercy of Allah and His blessing." She would reply, "And peace be upon you, my son, and the mercy of Allah and His blessing." Then he said, "May Allah have mercy on you as you raised me when I was a child." She answered, "May Allah have mercy on you as you were dutiful to me when I was old." Whenever he wanted to go inside, he would do something similar.