Musnad Ahmad 5:498

Waki' narrated to us, al-A'mash narrated to us, from 'Adi ibn Thabit, from Zirr ibn Hubaysh, from 'Ali, who said: "The Prophet, peace and blessings of Allah be upon him, made a covenant with me that none shall love me except a believer, and none shall hate me except a hypocrite."