What is the ruling on those who say that faith is a single part that neither increases nor decreases, and who declare as disbelievers those who say: "I am a believer, if Allah wills"?

The questioner : What is the ruling on those who say this statement...?

The Shaykh: So what is the ruling? What is it?

The questioner : ... .

The Shaykh: We rule that they are mistaken.

The questioner: Do we not declare them disbelievers?

The Shaykh: No, we do not declare them disbelievers, because if a declaration of disbelief is issued in error by a person through independent legal reasoning, and this reasoning is incorrect, then it is sufficient for us to rule that he is mistaken and not to respond to a declaration of disbelief with a similar declaration of disbelief. So what is the difference between us and them? They rushed and declared the Shafi'is and others disbelievers because of their error in understanding the meaning of faith. We do not err in the same way as they do, and we say that faith increases and decreases. And whoever is asked and says, "I am a believer, if Allah wills," is far better than the one who says, "I am a true believer." And whoever declares either group disbeliever is in error, if not in danger.