Disbelief, in the literary meaning is ‘to hide’ or ‘to conceal’ and in terminology it is the opposite of Islam. Every non-Muslim is considered as a disbeliever. As we mentioned, there are three conditions in fulfillment of Islam: (1) Testimony to the oneness of God, (2) Belief in resurrection and life after death and (3) Testifying to the messengership of Prophet Muhammad (s). But if one denies any or all of these principles, he is a disbeliever and the conditions of Islam will not be applicable to him.


Almighty Allah says in the Holy Quran:

وَمَن لَّمْ يُؤْمِن بِاللَّهِ وَرَسُولِهِ فَإِنَّآ أَعْتَدْنَا لِلْكَافِرِينَ سَعِيراً

And whoever does not believe in Allah and His Apostle, then surely We have prepared burning fire for the unbelievers.” (48:13)


And in another chapter, He says:

 يَأَيُّهَا الَّذِينَ ءَامَنُواْ ءَامِنُواْ بِاللَّهِ وَرَسُولِهِ وَالْكِتَبِ الَّذِي نَزَّلَ عَلَى رَسُولِهِ وَالْكِتَبِ الَّذِي أَنْزَلَ مِنْ قَبْلُ وَمَنْ يَكْفُرْ بِاللَّهِ وَ مَلئِكَتِهِ وَكُتُبِهِ ورُسُلِهِ وَالْيَوْمِ الْأَخِرِ فَقَدْ ضَلَّ ضَلَلاً بَعِيداً

O you who believe! believe in Allah and His Apostle and the Book, which He has revealed to His Apostle and the Book, which He revealed before; and whoever disbelieves in Allah and His angels and His apostles and the last day, he indeed strays off into a remote error.” (4:136)


And He says:

 وَيَقُولُ الَّذِينَ كَفَرُواْ لَسْتَ مُرْسَلًا قُلْ كَفَى‏ بِاللَّهِ شَهِيدَا بَيْنِى وَ بَيْنَكُمْ وَمَنْ عِنْدَهُ عِلْمُ الْكِتَبِ‏

And those who disbelieve say: You are not a messenger. Say: Allah is sufficient as a witness between me and you and whoever has knowledge of the Book.” (13:43)


In another verse, He says:

وَمَن يَدْعُ مَعَ اللَّهِ إِلَهاً ءَاخَرَ لَا بُرْهَنَ لَهُ بِهِ فَإِنَّمَا حِسَابُهُ عِندَ رَبِّهِ إِنَّهُ لَا يُفْلِحُ الْكَفِرُونَ

And whoever invokes with Allah another god - he has no proof of this - his reckoning is only with his Lord; surely the unbelievers shall not be successful.” (23:117)


On the basis of this, one who is a denier of God or prophethood of the Prophet of Islam or resurrection and life after death is a disbeliever. In the same way, if one has doubt in any or all of these principles, he is a disbeliever.


The Holy Quran says:

 وَلَا يَزَالُ الَّذِينَ كَفَرُواْ فِى مِرْيَةٍ مِّنْهُ حَتَّى‏ تَأْتِيَهُمُ السَّاعَةُ بَغْتَةً أَوْ يَأْتِيَهُمْ عَذَابُ يَوْمٍ عَقِيمٍ

And those who disbelieve shall not cease to be in doubt concerning it until the hour overtakes them suddenly, or there comes on them the chastisement of a destructive day.” (22:55)


Imam Ja’far Sadiq (a) said: One who doubts in the existence of God or His Messenger, is a disbeliever.[77]

Amirul Momineen (a) said: Do not fall into uncertainty, lest you fall into doubt and do not fall into doubt, lest you become a disbeliever.[78]

It is can be concluded for above verses and traditions that doubt in one of the principles of religion makes one liable to disbelief even though it might not be accompanied by verbal denial. But it can be concluded from some traditions that doubt that appears to a person in solitude does not make him a disbeliever; on the contrary, it is verbal denial, which makes him a disbeliever.

Muhammad bin Muslim says: I was seated to the left of Imam Ja’far Sadiq (a) and Zurarah was to his right. At that moment Abu Basir entered and asked: O Aba Abdullah, what is your view about one who has doubt in the existence of God? He replied: He is a disbeliever. He further asked: What if he has doubt in the prophethood of Prophet Muhammad (s)? He replied: He is a disbeliever. At that moment he turned to Zurarah and said: He becomes a disbeliever in case he denies.[79]

Zurarah has narrated from Imam Ja’far Sadiq (a) that he said: If people reserve their judgment about something they have no knowledge of without denying, they don’t become disbelievers.[80]

On the basis of this, if one has doubts in the existence of God or prophethood of Prophet Muhammad (s) or resurrection, but he does not deny in words and his aim is to investigate and not to deny; such a person will not be considered a disbeliever.

Confirmed denier: One of the causes of denial is negation of the fundamental principles of religion. It is said that if one denies one of the necessary principles of religion like the obligation of prayer or paying of Zakat etc., while he knows that the mentioned order is among the necessary commands of religion, he is a disbeliever, because through this act, he denies the oneness of God or the messengership of the Prophet of Islam. Therefore the criterion of denial is negation of one of the principles of faith and one who negates one of the fundamentals of faith is a disbeliever and the rules of disbelief would apply on him. But one, who accepts all these fundamentals and testifies to their correctness, is a Muslim and the rules of Islam are applicable on him.

On the basis of this, Shia and the four schools of Ahle Sunnat (Hanafi, Maliki, Shafei and Hanbali) are Muslims, since they have faith in the principles of religion.
Religious Rulings Apperatined to disbelief

Disbeliever is having special rules in Islam and some of them are as follows:

1. Muslim men and women cannot marry disbeliever men and women in a permanent marriage;

2. A disbeliever does not inherit from a Muslim.

3. A disbeliever is ritually impure (Najis).

[77] Al-Kafi, Vol. 2, Pg. 386
[78] Al-Kafi, Vol. 2, Pg. 399
[79] Al-Kafi, Vol. 2, Pg. 339
[80] Al-Kafi, Vol. 2, Pg. 388