kufr al-nifaq refers to a form of disbelief characterized by hypocrisy in faith. It occurs when an individual outwardly professes belief in Islam while secretly rejecting its core tenets. This duality can lead to a lack of sincerity in worship and a disconnect between one's actions and beliefs. In Islamic theology, kufr al-nifaq is considered a serious offense, as it undermines the integrity of faith. It is often associated with the hypocrites mentioned in the Qur'an, who are warned of severe consequences in the afterlife. Understanding this concept helps in recognizing the importance of sincerity in one's religious practice.