The true faith of whoever says sincerely 'There is no god but Allah'
Q 6: If a man having five wives or more dies, is he considered a Muslim for whom we can offer the Funeral Prayer after his death, although we know that Allah (Glorified be He) says (what means):
Then do you believe in a part of the Scripture and reject the rest? Then what is the recompense of those who do so among you, except disgrace in the life of this world
True Iman (Faith) is not established by saying, “La ilaha illa Allah (there is no god but Allah),” unless it is said sincerely from the heart. Allah does not accept the Shahadah (Testimony of Faith) unless it is sincere. In this world, anyone who pronounces the Shahadah should be treated unconditionally as a Muslim, even if they are not sincere when saying it, because we must accept what is apparent and Allah is the One Who handles what is inwardly hidden. Anyone who pronounces the Shahadah and then does something that nullifies it has committed Kufr (disbelief), like someone who deems lawful what is well-known to be unlawful in Islam despite being notified of its unlawfulness, such as: Zina (sexual intercourse outside marriage) or marriage between two Mahrams (unmarriageable relatives); or if someone nullifies it by intentionally abandoning Salah (prayer), although they have been informed of the ruling and advised of the unlawfulness of this; this is according to the most correct scholarly opinion. Another nullifier of the Shahadah is wearing a talisman, or an amulet that does not contain Qur’an, believing in its effectiveness. If it is believed that it is a means of cure or protection from the evil eye or Jinn, it is Haram (prohibited) but it does not nullify Islam. It is, however, one form of minor Shirk (associating others with Allah in His Divinity or worship). The Prophet (peace be upon him) said,
“Whoever wears an amulet, may Allah not fulfill it (i.e., his want) for him, and whoever wears a sea-shell, may Allah not give him peace.”
There is disagreement among the scholars regarding the permissibility of wearing amulets containing Qur’anic Ayahs. However, the preponderant scholarly opinion is that it is Haram, according to the general evidence to block the means that may lead to wearing other things. (Part No. 1; Page No. 99) Among the other nullifiers of Islam is seeking help from the dead, idols, other inanimate objects, or those who are absent - Jinn or humans - or the living who are present, in matters that none can do but Allah, and the like.May Allah grant us success. May peace and blessings be upon our Prophet Muhammad, his family, and Companions.