It is its fruit. This is when the servant, seeing that he stands with his Lord who is al-Qayyūm (the Self-Subsisting, the Truthful), becomes annihilated (fanāʾ) from all forms, and becomes absent from himself because he is not self-subsisting. This also means that the servant is delivered from the immersion in perceiving his own deeds and from the stain of concealing (his acts of worship). This state is the disappearance of the Sufi spiritual state (ḥāl). The malāmati is one who is at the station of ikhlas (sincerity), but cannot comprehend the reality of ikhlas. This is the clear difference between the malāmati and the Sufi. (ʿAwārif, 49)
Ṣıdk (truthfulness) is steadfastness and soundness in matters of religion. In terms of spiritual states, it is striving on the path of Allah. Such an act is the act of a person who has performed it with gayra (zeal). This is the strength of iman (faith). (Futūḥāt, II, 219)
Every servant must pay attention to the words he uses and speak only the truth. Ṣıdk fi'l-qawl (truthfulness in speech and word) is the most famous and manifest type of ṣıdk. One must also avoid taʿrīḍ (ostentation or veiled verbal attacks), for taʿrīḍ has been likened to lying. However, in some cases where there is a legitimate interest, taʿrīḍ may be necessary.
Ṣıdk of intention and will (ṣıdk al-niyya wa-l-irāda) is entirely related to ikhlas. If any pleasure of the nafs (the lower self) mixes with the act, the sincerity of intention becomes bāṭil (null and void). (Qudāma, 394)
Ṣıdk in determination (ṣıdk fi'l-ʿazm) and showing loyalty: The first is, for example, when a person says, "If Allah gives me wealth, I will give it all in charity." This is sincerity in determination. Sometimes there may be hesitation in this. The second is loyalty in determination. The nafs is generous in making promises, for there is no hardship in promising. But when the matter is realized and comes to the stage of implementation, the dominance of shahwa (desire) causes the determination to disappear.
Ṣıdk in deeds (ṣıdk fi'l-aʿmāl) is that it makes no difference whether the act is done openly or secretly. That is, the outward acts should not display states such as khushūʿ (humble reverence) that are not present inwardly, nor should the inward be in a state contrary to this. (Qudāma, 395)
Ṣıdk is the beginning of the matter; with it, matters are completed, and by it, affairs are set in order. The lowest degree of ṣıdk is the unity of inner reality and speech. Sahl al-Tustarī says: "Whoever adorns his own nafs or another's nafs cannot even smell the scent of ṣıdk." Dhū'l-Nūn says: "Ṣıdk is the sword that Allah has placed to cut through anything absolutely (mutlaqan)."
It is narrated from the exalted imam and gnostic (ʿārif) Ḥārith al-Muḥāsibī, may Allah sanctify his secret, that: The ṣādiq (truthful one) is he who, if all his reputation among people were to leave their hearts—because his qalb (heart) has found complete salāh (rectitude)—would not care at all; if he had good deeds weighing as much as a mithqāl, he would not wish people to know of them; and he would not be displeased if his bad deeds became known to people. For being displeased at this is proof that one desires increased reputation among people. This is not from the character of the ṣiddīqūn (the utterly truthful ones).
It is also said: When you ask Allah for ṣıdk, Allah gives you a mirror in which you can see the beauties of this world (dunyā) and the Hereafter.
It is narrated that Abū'l-Qāsim Junayd said: The ṣādiq is one who, forty times a day, is tested in ṣıdk.