حَدَّثَنَا يَحْيَى بْنُ آدَمَ حَدَّثَنَا ابْنُ مُبَارَكٍ عَنْ يَحْيَى بْنِ أَيُّوبَ عَنْ عُبَيْدِ اللَّهِ بْنِ زَحْرٍ عَنْ عَلِيِّ بْنِ يَزِيدَ عَنِ الْقَاسِمِ عَنْ أَبِي أُمَامَةَ عَنْ عَلِيٍّ رَضِيَ اللَّهُ عَنْهُ قَالَ كُنْتُ إِذَا اسْتَأْذَنْتُ عَلَى رَسُولِ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ إِنْ كَانَ فِي صَلَاةٍ سَبَّحَ وَإِنْ كَانَ غَيْرَ ذَلِكَ أَذِنَ
مسند امام احمد بن حنبل · Hadith 767
It was narrated that 'Ali (RA) said: When I asked permission to enter upon the Messenger of Allah (PBUH), if he was praying he would say Subhan Allah, and if not he would give permission.
Translated by Dr. Muhammad Muhsin Khan · Reviewed by Islamic University of Madinah · Published March 2020