How sound is the statement that an unbeliever is only he who knows in his heart of the existence of a God and then disbelieves out of denial, and that whoever utters phrases such as "God is the third of three" or "Christ is the son of God" is not an unbeliever if he was raised on that without knowing it in his heart, taking into consideration that verses of declaring one an unbeliever, such as His Almighty saying: "Certainly they disbelieved who said...", refer to those who said it with their hearts and knew it to be false, unlike those who said it without knowledge, following the example of the hadith "Whoever says there is no god but Allah shall enter Paradise" which does not apply to the hypocrite?

The statement by the author that a disbeliever is one who knows in their heart that God exists and then openly denies it is incorrect. Rather, a disbeliever is one who doubts God, or believes there is no god, or believes in Him but associates partners with Him. It is sufficient for a person to declare shirk (polytheism) for them to be judged as a disbeliever in this world, such as the Christians whom God judged to be disbelievers due to their shirk. Allah says: {Certainly, disbelievers are those who say, "Allah is the Messiah, son of Mary."} And whoever does not embrace Islam is a disbeliever and will abide eternally in Hellfire, as the Prophet (peace and blessings be upon him) said: "By the One in Whose hand is the soul of Muhammad, no one from this nation, be he a Jew or a Christian, hears of me and then dies without believing in that with which I was sent, except that he will be among the people of the Hellfire." As for the Hereafter, we do not definitively assert that a specific individual will enter Hellfire unless there is a specific text. We generally bear witness that believers are in Paradise and disbelievers are in Hellfire, but we do not bear witness for a specific individual unless there is a text. If the conditions for declaring someone a disbeliever are met, it is permissible to apply the term "disbelief" to that specific individual in this world, but in the Hereafter, the ruling is general.