Sunan Ibn Majah

It was narrated from Ishaq bin Qabisah from his father that :Ubadah bin Samit Al-Ansari, head of the army unit, the Companion of the Messenger of Allah (ﷺ), went on a military campaign with Mu'awiyah in the land of the Byzantines. He saw people trading pieces of gold for Dinar and pieces of silver for Dirham. He said: ""O people, you are consuming Riba (usury)! For I heard the Messenger of Allah (ﷺ) say: 'Do not sell gold for gold unless it is like for like; there should be no increase and no delay (between the two transactions).'"" Mu'awiyah said to him: ""O Abu Walid, I do not think there is any Riba involved in this , except in cases where there is a delay."" 'Ubadah said to him: ""I tell you a Hadith from the Messenger of Allah (ﷺ) and you tell me your opinion! If Allah brings me back safely I will never live in a land in which you have authority over me."" When he returned, he stayed in Al-Madinah, and 'Umar bin Khattab said to him: ""What brought you here, O Abu Walid?"" So he told him the story, and what he had said about not living in the same land as Mu'awiyah. 'Umar said: ""Go back to your land, O Abu Walid, for what a bad land is the land from where you and people like you are absent."" Then he wrote to Mu'awiyah and said: ""You have no authority over him; make the people follow what he says , for he is right