"a man entered the masjid, and the Messenger of Allah ﷺ was sitting in a corner of the mosque. He prayed, then he came and greeted him with Salam(peace), and he said: 'Wa 'alaikassalm."  

أَنَّ رَجُلاً دَخَلَ الْمَسْجِدَ وَرَسُولُ اللَّهِ ﷺ جَالِسٌ فِي نَاحِيَةِ الْمَسْجِدِ فَصَلَّى ثُمَّ جَاءَ فَسَلَّمَ فَقَالَ وَعَلَيْكَ السَّلاَمُ  

"Jibrail send (greetings of) Salam to you." She said: "Wa 'alahisalam wa rahmatullah (and upon him be peace and mercy of Allah)."  

أَنَّ رَسُولَ اللَّهِ ﷺ قَالَ لَهَا إِنَّ جِبْرَائِيلَ يَقْرَأُ عَلَيْكِ السَّلاَمَ قَالَتْ وَعَلَيْهِ السَّلاَمُ وَرَحْمَةُ اللَّهِ