Musnad Ahmad 32:1236

Rawh narrated to us, Shu'bah narrated to us, from Qatadah, from Anas ibn Malik, who said: The Messenger of Allah (peace and blessings of Allah be upon him) said: "Do not cut ties with one another, do not harbor hatred toward one another, and do not envy one another. And be, O servants of Allah, brothers."