You must know that _nafs_, etymologically, is the essence and reality of anything, but in popular language it is used to denote many contradictory meanings, e.g. “spirit”, “virility” (_muruwwat_), “body”, and “blood”. The mystics of this sect, however, are agreed that it is the source and principle of evil, but while some assert that it is a substance (_`ayn_) located in the body, as the spirit (_rúḥ_) is, others hold it to be an attribute of the body, as life is. But they all agree that through it base qualities are manifested and that it is the immediate cause of blameworthy actions. Such actions are of two kinds, namely, sins (_ma`áṣí_) and base qualities (_akhláq-i daní_), like pride, envy, avarice, anger, hatred, etc., which are not commendable in law and reason. These qualities can be removed by discipline (_riyáḍat_): e.g., sins are removed by repentance. Sins belong to the class of external attributes, whereas the qualities above mentioned belong to the class of internal attributes. Similarly, discipline is an external act, and repentance is an internal attribute. A base quality that appears _within_ is purged by excellent outward attributes, and one that appears _without_ is purged by laudable inward attributes. Both the lower soul and the spirit are subtle things (_laṭá´if_) existing in the body, just as devils and angels and Paradise and Hell exist in the universe; but the one is the seat of good, while the other is the seat of evil. Hence, resistance to the lower soul is the chief of all acts of devotion and the crown of all acts of self-mortification, and only thereby can Man find the way to God, because submission to the lower soul involves his destruction and resistance to it involves his salvation.[115] Footnote 115: Here the author cites Kor. lxxix, 40, 41; ii, 81 (part of the verse); xii, 53; and the Traditions: “When God wishes well unto His servant He causes him to see the faults of his soul,” and “God said to David, ‘O David, hate thy soul, for My love depends on thy hatred of it.’”