Not a believer whose neighbour is not safe
وَاللَّهِ لَا يُؤْمِنُ، وَاللَّهِ لَا يُؤْمِنُ، وَاللَّهِ لَا يُؤْمِنُ. قِيلَ: وَمَنْ يَا رَسُولَ اللَّهِ؟ قَالَ: الَّذِي لَا يَأْمَنُ جَارُهُ بَوَائِقَهُ
Wa-llahi la yu'min, wa-llahi la yu'min, wa-llahi la yu'min. Qila: wa man, ya Rasulallah? Qala: alladhi la ya'manu jaruhu bawa'iqah.
"By Allah, he does not believe. By Allah, he does not believe. By Allah, he does not believe. They said: Who, O Messenger of Allah? He said: The one whose neighbour is not safe from his harm."
Narrated by Abu Shurayh. Sahih al-Bukhari 6016
A short reflection
Three oaths. Belief is checked at the neighbour's door — before and after everything else.