Question:

There is a Christian (Kitābī) who is a monotheist and he believes in his Prophet and all the other Prophets; however, he does not say the kalimah “There is no god but Allah, and Muhammad is the Messenger of Allah.” What ruling does Islam apply to such a person? If he dies, can it be said, that he died on Imān?

Answer: حامدا ومصليا ومسلما

After the advent of the noble Messenger (Muhammad) ﷺ the only religion that can be called the Dīn of Islām is the one which is in accordance to the Qurān and the teachings of Prophet (Muhammad) ﷺ. This is also the only one accepted by Allāh. No other religion is accepted or a means of salvation. (Maʿāriful Qurān Vol.2 Pg.38)

والذي نفس محمد بيده لو بدا لكم موسى فاتبعتموه وتركتموني لضللتم عن سواء السبيل ولو كان حيا وأدرك نبوتي لاتبعني

“By the Being in Whose Hands is the life of Muhammad, if Mūsā was to appear before you and you all were to follow him and leave me, you would have gone astray from the straight path. If he was alive and witnessed my prophethood, he would have surely followed me.” (Mishkāt: 32)

The advent of the respected Prophet (Muhammad) ﷺ abrogated all previous religions. Therefore, salvation is not possible without believing in Prophet (Muhammad) ﷺ. Such an Imān (which was asked in the question) will not be valid. And Allāh Taʿālā knows best.

(Hazrat Muftī) Ahmed Khānpūrī (May Allāh preserve him.)

Mahmūdul Fatāwā Vol.1 Pg.319