The Messenger of Allah ﷺ said, "You will not enter Paradise until you believe, and you will not truly believe until you love one another. Shall I not guide you to something which, if you do it, you will love one another? Spread the greeting of peace among yourselves."
قال رسول الله ﷺ: لا تدخلون الجنة حتى تؤمنوا، ولا تؤمنوا حتى تحابوا، أولا أدلكم على شيء إذا فعلتموه تحاببتم؟ أفشوا السلام بينكم.
Muslim narrated it in the book of Faith (54), from Abu Bakr bin Abu Shayba, who said, Abu Muawiya and Waki narrated to us, from Amash, from Abu Salih, from Abu Hurairah, and he mentioned the hadith. In the narration of Jareer from Amash, "By the One in whose hand is my soul, you will not enter Paradise until you believe," similar to the hadith of Abu Muawiya and Waki.