Musnad Ahmad 26:822

Yunus narrated to us, Yazid ibn Zuray' narrated to us, Khalid narrated to us, from Abu Ma'shar, from Ibrahim, from Alqamah, from Abdullah, from the Prophet, peace and blessings of Allah be upon him, who said: "Let those among you who possess discernment and intellect be nearest to me, then those who are next to them, then those who are next to them. And do not differ, for your hearts will differ. And beware of the clamors of the marketplaces."