A Jew passed by Messenger of Allah ﷺ and said, "As-Samu 'Alaika." Messenger of Allah ﷺ said in reply, "We 'Alaika." Messenger of Allah ﷺ then said to his companions, "Do you know what he (the Jew) has said? He said, 'As-Samu 'Alaika.'" They said, "O Messenger of Allah ﷺ! Shall we kill him?" The Prophet, said, "No. When the people of the Book greet you, say: 'Wa 'Alaikum.'"  

سَمِعْتُ أَنَسَ بْنَ مَالِكٍ يَقُولُ مَرَّ يَهُودِيٌّ بِرَسُولِ اللَّهِ ﷺ فَقَالَ السَّامُ عَلَيْكَ فَقَالَ رَسُولُ اللَّهِ ﷺ وَعَلَيْكَ فَقَالَ رَسُولُ اللَّهِ ﷺ أَتَدْرُونَ مَا يَقُولُ قَالَ السَّامُ عَلَيْكَ قَالُوا يَا رَسُولَ اللَّهِ أَلاَ نَقْتُلُهُ قَالَ لاَ إِذَا سَلَّمَ عَلَيْكُمْ أَهْلُ الْكِتَابِ فَقُولُوا وَعَلَيْكُمْ  

A group of Jews came to Messenger of Allah ﷺ and said, "As-samu 'Alaika " (Death be on you), and I understood it and said to them, "Alaikum AsSamu wa-l-la'na (Death and curse be on you)." Allah's Apostle said, "Be calm! O ʿAisha, for Allah loves that one should be kind and lenient in all matters." I said. "O Messenger of Allah ﷺ! Haven't you heard what they have said?" Messenger of Allah ﷺ said, "I have (already) said (to them), 'Alaikum (upon you).' "  

دَخَلَ رَهْطٌ مِنَ الْيَهُودِ عَلَى رَسُولِ اللَّهِ ﷺ فَقَالُوا السَّامُ عَلَيْكَ فَفَهِمْتُهَا فَقُلْتُ عَلَيْكُمُ السَّامُ وَاللَّعْنَةُ فَقَالَ رَسُولُ اللَّهِ ﷺ مَهْلاً يَا عَائِشَةُ فَإِنَّ اللَّهَ يُحِبُّ الرِّفْقَ فِي الأَمْرِ كُلِّهِ فَقُلْتُ يَا رَسُولَ اللَّهِ أَوَلَمْ تَسْمَعْ مَا قَالُوا قَالَ رَسُولُ اللَّهِ ﷺ فَقَدْ قُلْتُ وَعَلَيْكُمْ