The reciter: Abu Bakr ibn Abi Shaybah narrated to us, Abu Mu'awiyah and Waki' narrated to us, from al-A'mash, from Abu Salih, from Abu Hurayrah, who said: The Messenger of Allah (peace and blessings be upon him) said:
You shall not enter Paradise so long as you do not affirm belief (in all those things which are the articles of faith) and you will not believe as long as you do not love one another. Should I not direct you to a thing which, if you do, will foster love amongst you: (i. e.) give currency to (the practice of paying salutation to one another by saying) as-salamu alaikum.
لا تدخلون الجنّة حتّى تؤمنوا ، ولا تؤمنوا حتّى تحابّوا ، أولا أدلّكم على شيءٍ إذا فعلتموه تحاببتم ؟ أفشوا السّلام بينكم Sahih Muslim 54a