Who Is Kafir With Whom Muslims Are Prohibited To Marry?
I would like to add.. since neither the questioner nor answerer mentioned it that Ghamidi sahab was referring to those who consider themselves as Muslims.. let’s say the Ahmedis, we have no right to declare them “Kafir” especially if they qualify the criteria of “believer” as per Quran (i.e. to believe in Allah, His Messengers, His Angels, His Book, and Last Day). Declaring atheists as Kafir is perfectly fine. While Non-Muslims from other religions, among them could be kafirs and some successful, only Allah (swt) will judge. Unless we know specific information about an individual (or a particular group) with a certain public/declared Kufr, we cannot declare anyone Kafir.