Shurūd is the withdrawal of attributes from encountering realities and from adhering to rights. (Lumaʿ, 446)
The meaning of shurūd is to seek the Real (al-Ḥaqq) by escaping from afflictions, veils (ḥijāb, spiritual barriers), and instability regarding the veils. For all tribulations that befall the seeker (ṭālib) come from the veils. For this reason, Sufis call the means, journeys, and all the efforts that seekers undertake to lift the veils shurūd. The more anxious a person is at the beginning of the quest, the greater their attainment (wuṣūl) and steadfastness (tamkīn) at the end. (Hujwīrī, 472)
shurūr (pl. of sharr, evils) are of two kinds: Essential evil is that which is itself an act of disobedience (maʿṣiyya, sin), such as what Allah has forbidden. Non-essential evil is that which Allah has prohibited not by making it unlawful, but as a means of discipline (taʾdīb, for training). Permissible acts (mubāḥ) done out of desire are of this kind. The first strengthens the obligatory (farḍ) whose abandonment entails punishment. The second, when abandoned, results in being prevented, called to account, blamed, and reproached, and is a matter of virtue and etiquette. (Minhāj, 27)
Evils are of three types: those that harm, those that are ugly, and those that cause pain. Each of these has two kinds. One of these is absolute (muṭlaq), like wisdom (ḥikma), which combines all three qualities in good: it is beneficial, beautiful, and pleasant. Ignorance, which combines all three in evil, is harmful, ugly, and painful.
The second is restricted (muqayyad), combining only some of these qualities. Sometimes, as in cutting off an extra finger or removing a cyst outside the body (wujūd), it is beneficial but painful. Sometimes, as with naivety or foolishness, it is beneficial but ugly, for such a person is at ease due to lack of intellect. Sometimes, as in throwing cargo overboard out of fear of sinking, it is beneficial in one respect and harmful in another: harmful for the goods, beneficial for the salvation of the self (nafs).
That which is beneficial is also of two kinds: that which is necessary (ḍarūrī), such as virtues of the self and attaining happiness in the Hereafter, and that which is not itself necessary but substitutes for something necessary, such as oxymel (serkancabīn, honey and vinegar syrup) to calm bile. (Mīzān, 92)