قَالَ رَسُولُ اللَّهِ ص إِذَا لَقِيَ أَحَدُكُمْ أَخَاهُ فَلْيُسَلِّمْ عَلَيْهِ وَ لْيُصَافِحْهُ فَإِنَّ اللَّهَ عَزَّ وَ جَلَّ أَكْرَمَ بِذَلِكَ الْمَلَائِكَةَ فَاصْنَعُوا صُنْعَ الْمَلَائِكَةِ.
“The Messenger of Allah has said, ‘Whenever any of you meets his Muslim brother (in belief) he should offer him the greeting of peace and shake his hand; Allah, the Most Majestic, the Most Holy, has honored the angels with it and you should also do what the angels do.’”