Ali Ibnul Husayn Bin Ali Bin Abee Taalib (rahimahullaah) used to sit with Aslam the freed slave of Umar (radiyallaahu-anhu); so a man from Quraish said to him: “You leave Quraish and sit with a slave of the clan of Adiy?” So he said: “Indeed a man sits where he benefits”
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[At-Tabaqaat Al-Kubra 5/111]