Sayyiduna Abu Umamah (may Allah be pleased with him) said that the Messenger of Allah (peace and blessings be upon him) said: "The sale of singing slave-girls is not lawful, nor is selling them lawful; trading in them is not permissible either, and consuming their price is unlawful." And in one narration Bakr bin Mudar reports from the Messenger of Allah (peace and blessings be upon him) that he (peace and blessings be upon him) said: "Do not sell singing slave-girls, nor buy them, nor teach them. There is no good in trading in them, and their price is unlawful." And it was concerning such things that this saying of Allah Almighty was revealed: "And among the people is he who buys idle talk to mislead from the way of Allah without knowledge and takes it in ridicule. Those will have a humiliating punishment" [Surah Luqman: 6].
Hadith Referenceالسنن الكبرى للبيهقي / كتاب البيوع / 11056