The Prophet (ﷺ) said, "By Allah, he is not a believer! By Allah, he is not a believer! By Allah, he is not a believer." It was asked, "Who is that, O Messenger of Allah?" He said, "One whose neighbour does not feel safe from his evil".
[Al-Bukhari and Muslim].
Another narration of Muslim is: Messenger of Allah (ﷺ) said, "He will not enter Jannah whose neighbour is not secure from his wrongful conduct".
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