Sunan Abi Dawud, Hadith 2932 ⓘ

Narrated Ibn Ishaq: Sahib maks means one who (receives) tithes (from) people.

حَدَّثَنَا مُحَمَّدُ بْنُ عَبْدِ اللَّهِ الْقَطَّانُ، عَنِ ابْنِ مَغْرَاءَ، عَنِ ابْنِ إِسْحَاقَ، قَالَ الَّذِي يَعْشُرُ النَّاسَ يَعْنِي صَاحِبَ الْمَكْسِ ‏.‏

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also referenced under: Hadith 2938 (DarusSalam)