What is the ruling on one who claims to be the Awaited Mahdi while not believing that Muhammad is the Seal of the Messengers, and does this constitute disbelief, and what is the ruling on his marriage to a Muslim woman, and what is the ruling on one who believes him and helps him spread his claims, and does one who marries his daughter to this man commit a grave sin?

The Mahdi is a man from the nation of Muhammad, peace and blessings be upon him. He does not exist now, and his name is Muhammad ibn Abdullah. He will appear at the end of time, and he will fill the earth with fairness and justice. Jesus, peace be upon him, will pray behind him. He will not claim to be the Mahdi himself, and anyone who claims to be the Mahdi now is a liar.

Whoever does not believe that Muhammad, peace and blessings be upon him, is the Seal of the Messengers is a disbeliever, because he has denied what is explicit in the Qur'an, the Sunnah, and the consensus of the scholars. Numerous sacred texts have confirmed the sealing of prophethood and messengership with Muhammad, peace and blessings be upon him. And whoever claims otherwise, or believes anyone who does, or aids in spreading such a claim, is a disbeliever and an apostate from Islam.

It is not permissible to marry a Muslim woman to a disbeliever or an apostate. And whoever marries his daughter to this apostate, while knowing his condition, has committed a grave sin, and may even be a disbeliever if he considers it permissible or agrees with the apostate's apostasy.