Kufr committed by Muslim

Can “kufr” be committed by those who believe in Allah?

This post reviews whether the word “kufr” applies only to the person who denies the existence of Allah / God or if it can also apply to those who believe in Allah. By studying the Quran, one can notice that the word “kufr” can also apply to those who may believe in Allah as a being but deny (directly or through their actions) in all of Allah’s powers. Sheikh Modudi provides an explanation by pointing out the example in Surah Al-Kahf of the conversation between two individuals where one of them was blessed with Allah’s bounties. In his conversation with his companion, he states that even if he meets Allah, he expected to enter paradise. On hearing this, his companion said the following (as mentioned in the Quran):

His companion rebuked him during the conversation, saying, “Do you disbelieve in the Being Who has created you from clay (i.e. your father Adam), then from out of Nutfah (mixed semen drops of male and female discharge) and then shaped you as a man?
Quran (Surah Al-Kahf, Verse 37)

Sheikh Modudi states that “This shows that “unbelief ” in Allah is not confined to the denial of the existence of God in so many words, but arrogance, pride, vanity and the denial of the Hereafter are also kufr. Although that person did not deny the existence of Allah, his companion charged him with unbelief in Allah. This is because the person, who considers his wealth and his grandeur etc., to be the fruits of his own power and capability and not the favors of Allah, and who thinks that they are everlasting and none can take than away from him and that he is not accountable to anyone, is guilty of “unbelief in AIIah”, even though he might profess belief in Him, for he acknowledges Allah as a Being and ‘not as his Master, Owner and Sovereign.’
In fact, belief in Allah demands not merely the profession of His existence but also the acknowledgment of His Sovereignty, Mastery, Rule and the like.