عن عمران بن حصين رضي الله عنه أن رجلا جاء إلى النبي صلى الله عليه وسلم فقال السلام عليكم قال قال النبي صلى الله عليه وسلم عشر ثم جاء آخر فقال السلام عليكم ورحمة الله فقال النبي صلى الله عليه وسلم عشرون ثم جاء آخر فقال السلام عليكم ورحمة الله وبركاته فقال النبي صلى الله عليه وسلم ثلاثون (سنن الترمذي #2689، سنن أبي داود #5195)

Hazrat ‘Imraan bin Husain (radhiyallahu ‘anhu) reports that a man once came to Rasulullah (sallallahu ‘alaihi wasallam) and greeted him saying, “Assalaamu ‘alaikum”. After replying to his salaam, Rasulullah (sallallahu ‘alaihi wasallam) said, “Ten (i.e. he has earned ten rewards)”. Thereafter, another man came and greeted Rasulullah (sallallahu ‘alaihi wasallam) saying, “Assalaamu ‘alaikum warahmatullah”. After replying to his salaam, Rasulullah (sallallahu ‘alaihi wasallam) said, “Twenty (i.e. he has earned twenty rewards)”. Finally, a third person came to Rasulullah (sallallahu ‘alaihi wasallam) and greeted him saying, “Assalaamu ‘alaikum warahmatullahi wabarakaatuh”. After replying to his salaam, Rasulullah (sallallahu ‘alaihi wasallam) said, “Thirty (i.e. he has earned thirty rewards)”.