—exalted be He—says: “Whoever seeks a religion other than Islam, it will never be accepted from him, and in the Hereafter he will be among the losers.” (Aal ‘Imran 3:85). Hence, anyone who does not believe in the mission of Muhammad ﷺ and adopts a religion other than Islam is an unbeliever. One must therefore stay alert to this call and never be taken in by it, for the true faith is the religion of Islam. Admittedly, all the Messengers preached Islam, and those who truly followed Moses (peace be upon him) or Jesus (peace be upon him) were Muslims. Yet those in either community who altered and deviated, committing various kinds of disbelief, thereby became unbelievers—just as they disbelieved by refusing to follow Muhammad ﷺ.

The Christians became disbelievers by worshipping the Messiah and his mother and by claiming that he is Allah or the son of Allah; they further disbelieved by denying Muhammad ﷺ. Even had they remained upright upon their original religion but then failed to believe in Muhammad ﷺ, they would still have been unbelievers, and anyone who dies in that state is destined for the Fire. This is confirmed in the authentic hadith of the Prophet ﷺ: “By Him in Whose hand is the soul of Muhammad, no one from this ummah—Jew or Christian—hears of me and then dies without believing in that with which I have been sent, except that he will be among the inhabitants of the Fire.” (1)

We observe that the first and second nullifiers pertain to the testimony that there is no deity but Allah; each of them contradicts that testimony. The third nullifier, however, contradicts both testimonies.