Is saying that a specific disbeliever, if he dies, will be in Hell considered an overstepping of bounds with regard to Allah, as is done by some of the takfiri people of innovation?

To definitively assert that a specific person will enter Hellfire requires a particular textual (shar‘i) proof concerning that individual. No one is testified to be in Hellfire except those whom revelation has testified for, with the definitive understanding that whoever dies as a disbeliever is indeed among the people of Hellfire. To assert definitively that a specific person will enter Hellfire is tantamount to "presuming upon God" (al-ta'alli 'ala Allah), which is forbidden, based on the Prophet's (peace be upon him) statement: "Who is it that presumes upon Me that I will not forgive so-and-so? Indeed, I have forgiven so-and-so and invalidated your deeds." Therefore, it is not permissible for anyone to assert definitively about Paradise, Hellfire, or the lack of forgiveness, except for those about whom a text has been revealed.