Musannaf Ibn Abi Shayba 28:393

Ibn ‘Ulayyah narrated to us, from al-Jurayri, from Abu Nadrah, from Abu Firas, who said: ‘Umar ibn al-Khattab delivered a sermon and said: "Behold, by Allah, I do not send my governors to you to strike your skins nor to take your wealth. Rather, I send them to you to teach you your religion and your Sunnah. So whoever has anything other than that done to him, let him report it to me, for by Him in whose hand is my soul, I will surely exact retribution for him from him." ‘Amr ibn al-‘As stood up and said: "O Commander of the Faithful, have you considered if a man among the Muslims is over some subjects and he disciplines some of his subjects, would you exact retribution for him from him?" He said: "Yes, by Him in whose hand is the soul of ‘Umar, I will surely exact retribution for him from him. Why would I not exact retribution for him from him, when I have seen the Messenger of Allah (peace and blessings of Allah be upon him) exact retribution from himself?" "Behold, do not strike the Muslims, lest you humiliate them. Do not withhold their rights from them, lest you cause them to disbelieve. Do not keep them gathered in the military camps (for too long), lest you tempt them. And do not settle them in the thickets (of the wilderness), lest you cause them to be lost."