Kafara (or Kufr) in its linguistic sense means "to cover" or "to hide," but theologically it refers to the rejection of faith in Allah, His prophets, and the message of Islam. A person who commits Kufr is known as a Kafir. It encompasses not only outright atheism but also polytheism (Shirk) and the denial of any fundamental pillar of the faith. Islam teaches that faith is a gift of guidance, and to "cover" that truth out of arrogance or stubbornness is a grave spiritual error that carries consequences in the Hereafter. The root of kufr means to cover or conceal. A farmer is called a kafir because he covers the seed with soil. In a spiritual sense, a kafir is one who covers the truth, concealing what is naturally known about God. Kufr is of different types: kufr al-inad (rejection out of stubbornness), kufr al-juhud (denial out of ignorance), kufr al-nifaq (hypocrisy), and kufr al-ni'mah (ingratitude for blessings). The Quran warns: "Indeed, those who disbelieve,it is the same for them whether you warn them or do not warn them,they will not believe" (2:6). Kufr is a serious matter. It is the only sin Allah does not forgive if one dies upon it (4:48). However, the door of repentance is open; if one leaves kufr and embraces Islam, their past sins are forgiven. For believers, kufr is to be avoided. They are grateful for the gift of faith and seek to protect it. They do not judge others as kuffar lightly, for only Allah knows what is in hearts. The believer strives to be among those who believe, and hopes for Allah's mercy.