Praise be to Allah.
Kufr takes different forms. The Murji’ah and other followers of bid’ah (reprehensible innovation) say that kufr is only based on disbelief. But this view is contrary to the evidence and contrary to the truth. It is known that the Messengers were sent with miracles and proof to which hearts submitted. It is rare indeed that people believed that what the Prophets brought was false; most instances of kufr stemmed from arrogance, rejection and stubbornness. Allaah mentioned that Quraysh did not disbelieve the Prophet (peace and blessings of Allaah be upon him), “but it is the Verses (the Qur’aan) of Allaah that the Zaalimoon (polytheists and wrongdoers) deny” [al-An’aam 6:33 – interpretation of the meaning]. This happens very often. Hence the scholars divided kufr into various types: the kufr of negligence and not caring; the kufr of arrogance and pride; the kufr of disbelief; the kufr of hypocrisy; the kufr of doubt. There is a great deal of evidence to that effect in the Book of Allaah and the Sunnah of His Messenger (peace and blessings of Allaah be upon him). The story of Abu Taalib and the Prophet (peace and blessings of Allaah be upon him) is clear; he believed in him and he used to say, “Our son does not tell lies,” but he was still a kaafir, because he never made a statement of faith or followed it up with actions.