Sufyân ibn Husayn al-Wâsitî narrates:

“I spoke ill of a person in the presence of Iyâs bin Mu’âwiyah al-Muzanî who was the judge of Basra, a Tâbi’î and a very intelligent person. He looked straight in my face and asked

Did you wage war against the Romans?’
I replied: “No”.

He asked, 'Did you wage war against Sind, India and the Turks?'
I replied “No”,

‘How is it then, that the Romans, the Sindis, the Indians and the Turks are safe from you whilst your own Muslim Brother is not safe from you?”

Sufyan narrates: I never did this again

Ibn Kathîr: al-Bidâyah wan-Nihâyah,
Volume 9: Page 336

It is related that once in the presence of Imâm Mâlik somebody praised the governor – consequently Imâm Mâlik became angry and said:

“Beware lest these people beguile you through their praise of you. Whoever praises you and says good about you which is not in you is just as likely to say evil about you which is not in you.”

“Be on your guard about claiming for yourself or being pleased with what one of them says to your face…for you know yourself better than they do.”

“I have heard that a man praised another man in the presence of the Prophet صلى الله عليه و سلم and the Prophet صلى الله عليه و سلم said to him, ‘You have cut his back’ or ‘his neck’. If he had heard it, he would not have prospered.

The Prophet صلى الله عليه و سلم said, “Throw dirt in the faces of people who praise too much”.