once
قَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم: ((لاَ تَدْخُلُوا الْجَنَّةَ حَتَّى تُؤْمِنُوا، وَلاَ تُؤْمِنُوا حَتَّى تَحَابُّوا، أَوَلاَ أَدُلُّكُم عَلَى شَيْءٍ إِذَا فَعَلْتُمُوهُ تَحَابَبْتُم، أَفْشُوا السَّلاَمَ بَيْنَكُمْ)).
Meaning
The Messenger of Allah said: ‘You shall not enter paradise until you believe, and you shall not believe until you love one another. Shall I not inform you of something, if you were to act upon it, you will indeed achieve mutual love for one another? Spread the greeting amongst yourselves.
Source and references
Hisn al-Muslim, entry 224.The reference is copied from the edition; separate editorial verification is not complete yet.
Source edition: Fortress of the Muslim. Open source ↗