Al-ʿAbbas bin Ghālib al-Warrāq said:
I said to Aḥmad bin Ḥanbal: “O Abū ʿAbdullāh, if I am sat in a gathering in which no one knows the Sunnah but me and an innovator speaks, shall I refute him?” He said, “No, do not task yourself to do this, but merely inform (the gathering) of the Sunnah. Do not debate.” I then repeated it to him again, and he said: “I do not see you except as a disputer.”
This is great advice for the one who finds himself in such situations. When things are mentioned that go against the Sunnah, a person should not enter into a debate but simply mention what the Sunnah is, and simply say, “This is what is known from the Sunnah about this affair” and not enter into any disputation or argumentation.
Note also how the questioner tried to repeat his request and Imām Aḥmad told him that he appears to be a person whose main interest is just to dispute. This shows that it is not from the way of a person who is truly grounded in the Sunnah to seek out disputes.
Rather, one who seeks disputes and debates is exactly what Imām Aḥmad said, “A disputer”—meaning one whose foundation is disputation, not one whose foundation is the Sunnah.