It was narrated from Abu Hurairah(RA) that the Messenger of Allah(ﷺ) said:"By the One in Whose Hand is my soul, you will not enter Paradise until you believe, and you will not believe until you love one another. Shall I not tell you of something which, if you do it, you will love one another? Spread (the greeting of) peace among yourselves

English translation · Sunan Ibn Majah