Girr billah (being deluded by Allah) is a type of delusion and heedlessness that can arise from disbelievers, sinful Muslims, those who are devoted to much worship and possess religious authority (ṣāḥib), and indeed from anyone who is deceived by anything. In this way, one neglects Allah's command. The person's fear and awe of Allah diminish. Being deluded by Allah is when the nafs (the lower self) deceives the servant either through what Allah has granted him, or by means of Allah's name rajāʾ (hope), or by a small amount of worship and knowledge. Many devoted worshippers (ʿābid) have been deceived in this way. Indeed, even if Allah accepts such a person among the muḥsinūn (those who excel in spiritual excellence), that person may still disobey Allah; yet he considers himself among the muḥsinūn, or, even while denying Allah, he imagines himself among those who have attained hudā (guidance), or, being deluded, he knowingly persists in disobedience, but assumes that he will attain maghfira (forgiveness) and will not be subjected to punishment, thinking he will be saved. The delusion of the disbelievers is that their nafs and their enemies (the shayṭān) deceive them by preferring the outward aspect of the dunyā (this world) over the Hereafter. (Riʿāya, 270)
gişâ and gişâvet: Gişâ and gişâvet are the rust and hardness of the qalb (the heart) that accumulate on the mirror of the heart, veiling its surface and binding a person's spiritual insight (baṣīra). (Kāshānī, 167; Jāmiʿ, 91)