One who declares some of the misguided and some of the sinners to be disbelievers, but prays with them, what is your opinion of him?

Question:
May Allah reward you with good, and may He do you good. One who declares some of the misguided and some of the sinners to be disbelievers, but prays with them, what is your opinion of that?

Answer:
We said that it is not the right of every person to declare disbelief against one who testifies that there is no god but Allah and that Muhammad is the Messenger of Allah, unless he has knowledge of the types of apostasy and the nullifiers of Islam. As for the ignorant person, he does not enter into the domain of declaring someone a disbeliever, so that he does not declare a Muslim a disbeliever without right. However, if he knows the nullifiers of Islam and the causes of apostasy, and it is established for him that this person is committing one of them, then it is not permissible for him to pray behind him, because he is a committer of it. Yes.