Islam promote peace and harmony

وعن أبي هريرة رضي الله عنه أن النبي صلى الله عليه وسلم قال‏:‏ ‏"‏ والله لا يؤمن، والله لايؤمن، والله لا يؤمن‏!‏‏"‏ قيل‏:‏ من يا رسول الله‏؟‏ قال‏:‏ ‏"‏ الذي لا يأمن جاره بوائقه ‏!‏ ‏"‏ ‏(‏‏(‏متفق عليه‏)‏‏)‏‏.‏ 
وفي رواية لمسلم‏:‏ ‏"‏ لايدخل الجنة من لا يأمن جاره بوائقه‏"‏‏.‏

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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