Ibn Ajiba's The Book of Ascension to the Essential Truths of Sufism
Fear (khawf) is the heart’s distress at confronting what it abhors or losing what it desires. Its frutis should be renewed effort to live in obedience to God and avoid transgressions. Lacking this, it is only pretension.
The generality fear punishment or losing some reward [in the next world]; the elect fear divine reproach or that they will cease to draw nearer to God; and the elect of the elect fear being veiled from God by their poor comportment.
Forms of the verbal root kh-w-f, “to be afraid”, occur in the Quran approximately 120 times.