There are two aspects of disbelief:

There are two aspects of disbelief:

The major disbelief Al-Kufr al-akbar:

This aspect excludes one completely from the fold of Islam. There are five types of this major disbelief:

a. Kufr at-takdhib.

This implies disbelieving the divine truth or denying of any of the articles of Faith.

Almighty Allah says: "Then who does more wrong than one who utters a lie against Allah and denies the truth when it comes to him. Is there not in Hell an abode for the disbelievers?"
Surah 39:32

b. Kufr al-iba wat takkabur ma'at-tasdig.

This implies rejection and arrogance to submit to Allahs Commandments after conviction of their truth.

Almighty Allah says: "And remember when we said to the angels: Postrate yourselves before Adam'. And they postrated except IBLIS, he refused and was proud and was one of the disbelievers."
Surah 2:34

c. Kufr ash-shakk waz-Zann.

This implies doubting or lacking of conviction in the six articles if the faith.

Almight Allah says: "And he went into his garden in the state of pride and disbelief unjust to himself. He said:' I think not that this will ever perish. And i not think that the Hour will ever come, and if indeed I am brought back to my lord I surely shall find better than this when i return to Him.'
His companion said to him during the talk with him: "Do you disbelief in Him Who has created you out of dust,then out of NUTFAH, then fashioned you into a man? But as for my part i believe that He is Allah ,my lord and none shall I associate as apartner with my Lord.' "
Surah 18:35-38

d. Kufr al-I'rad.

This impies turning away from the Truth knowingly or deviating from the obvious signd which Allah has revealed.

Almighty Allah says: "We created not the Heavens and the earth and all that is between them except with truth and for an appointed term. But those who disbelieve turn away from that whereof they are warned."
Surah 46:3

e. Kufr an-Nifaq.

This implies hypocritical disbelief.

Almight Allah says: "They have made their oath a screen.Thus they hinder men from the path of Allah. Verily, evil is what they used to do.That is because they believed, then disbelieved, therefore their hearts are sealed. They understand not."
Surah 63:2-3

2. The minor disbelief:

This aspect of disbelief does not exclude one from the fold og Islam. It is also termed as Kufr-Ni'mah.

This implies disbelief manifesting itself in ungratefulness for Allah's blessings of Favours.

Almighty Allah says: 'And Allah puts forward the example of a township Makkah, that dwelt secure and well-content; its provision coming to it in abundance from every place, but it denied the Favours of Allah. So Allah made it taste extreme of hunger famine and fear, because of that evil denying Prophet Muhammad pbuh which they used to do.
Surah 16:112