Answered by Shaykh Hamza Karamali, SunniPath Academy Teacher
If someone dislikes being praised (by, for example, having his good
deeds mentioned in front of other people), is it considered
backbiting or slander for me to mention such things to other people?
In the Name of Allah, Most Merciful and Compassionate
It is not unlawful to mention someone’s praiseworthy traits in their absence, even if they dislike it.
Ibn Hajar mentions that backbiting means for one to say something about someone that is either (a) disliked in Sacred Law or (b) disliked according to the common acknowledgment of people (Tuhfa, 7.213).
Mentioning that someone prays the night-vigil prayer (tahajjud) or that he is handsome, for example, is neither disliked in Sacred Law, nor is it something that
people customarily dislike, and therefore would not constitute backbiting.
And Allah knows best.