Musnad Ahmad 31:186

Yahya ibn Adam narrated to us, Fudayl narrated to us, from Atiyyah, from Abu Sa’id, who said: The Messenger of Allah (peace and blessings of Allah be upon him) said: "Indeed, the most beloved of people to Allah, the Almighty and Majestic, on the Day of Resurrection, and the closest of them to Him in seating, is a just leader. And indeed, the most hateful of people to Allah on the Day of Resurrection, and the severest of them in punishment, is a tyrannical leader."