Mujahid on Backbiting: Speak as you like to be spoken of

Al-Ghazali reported: Mujahid, may Allah have mercy on him, said, “Do not mention your brother in his absence except how you would love for him to mention you in your absence.”

Source: Iḥyā ‘Ulūm al-Dīn 2/181

عن الغزالي قال مجاهد رحمه الله لا تذكر أخاك في غيبته إلا كما تحب أن يذكرك في غيبتك

2/181 إحياء علوم الدين