Bulugh al-Maram, Book 11, Hadith 1311 (In-Book)

At-Taialisi transmitted on the authority of 'Amro bin al-'As (RAA), ‘The right of giving protection to non-Muslims is extended to the most humble of the believers (and all Muslims must respect it and give him support).’

وَلِلْطَيَالِسِيِّ: مِنْ حَدِيثِ عَمْرِوِ بْنِ الْعَاصِ: { " يُجِيرُ عَلَى اَلْمُسْلِمِينَ أَدْنَاهُمْ" } 1‏.‏ ‏1 ‏- صحيح بشواهده.‏ رواه أحمد ( 4 / 197 )‏.‏

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also referenced under: Book 11, Hadith 1338 (English)