Hadith 8:5
Rafi' b. Khadij reported God’s Messenger as saying, "The price paid for a dog is impure, the hire paid to a prostitute is impure, and the earnings of a cupper are impure.” Muslim transmitted it.
وَعَنْ رَافِعِ بْنِ خَدِيجٍ قَالَ: قَالَ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ: «ثَمَنُ الْكَلْبِ خَبِيثٌ وَمَهْرُ الْبَغِيِّ خَبِيثٌ وَكَسْبُ الْحَجَّامِ خَبِيثٌ» . رَوَاهُ مُسلم
Original Reference: Mishkat al-Masabih 2763