Musnad Ahmad 770:16

Hajjaj narrated to us, Shu'bah narrated to me, from 'Ali ibn Mudrik, who said: I heard Abu Zur'ah narrating from Jarir—and he is his grandfather—from the Prophet, may Allah bless him and grant him peace, that he said during the Farewell Pilgrimage: "O Jarir, ask the people to be silent." Then he said in his sermon: "Do not return after me as disbelievers, striking the necks of one another."