The soul (an-nafs) is a substance that is essentially free of matter but which is in close connection with it in its acts and functions; it is the origin or essence of something or its self. There have been those who have used it in the sense of the spirit or the heart or the body, or in the sense of lusts or the mechanism through which Satan penetrates humans, or even in the sense of reason. In religious terminology, an-nafs, or the soul, is the origin or center of certain states or faculties such as lusts, anger, ill will, grudge, hatred, and irritation, and it is a transformable, reformable, and refinable mechanism connected to human corporeality.
The soul has a constant, experienced connection between the body and the spirit. It is through this connection that humans receive, recognize, and distinguish their outer and inner sense-perceptions and go beyond the corporeal realm into metaphysical worlds. It is again through this connection that any state, experience or gift that occurs in the spirit leaves its imprint upon the body and provokes it to move in a certain direction. Just as every influence on the spirit makes itself felt on the body, so too every state of and effect on the body shows itself on the horizon of the spirit.
For example, thinking of something which is nauseating may produce an urge to vomit. Certain events which touch the spirit and rouse distress may cause physical ailments that we call psychosomatic illnesses. The reaction that the sense of taste shows at the mention of something sweet or sour or bitter is also this same sort of impression. In short, there is a continuous interactive relationship between the spirit and the body. Similarly, evil conceptions and disagreeable manners and actions impress not only the body but also the spirit, while agreeable thoughts and considerations, and the plans and projects that are undertaken to please God Almighty, and the mentioning of the Divine Being by the heart and tongue all produce expansion and exhilaration in the spirit. It frequently occurs that even if we are not aware of it, this state gains some sort of luminosity and surrounds the entire horizon of the spirit by means of the spiritual intellect. It rouses the "secret" and begins to manifest itself in the metaphysical depths of human existence in different modes. Also, whenever the body expresses its submission to the Ultimate Truth through the acts of worship and obedience and lives in accordance with the purpose of its existence, deepening in belief through worship or religious acts and crowning its worship with excellence and awareness of God's omnipresence, the breezes of great happiness and joy begin to blow in the spirit. Hope and expectation stir up eagerness for God, the Ultimate Truth, and the acts leading to consciousness and awe of God produce feelings of respect, self-possession, and wakefulness in the spirit. As a result, like the seas vaporizing to rise and form the clouds, and the clouds raining on the earth, and rains forming rivers and torrents that flow into the sea, there appear continuous currents between the body and the spirit.
Amidst such mutual influences between the spirit and the body, it is possible for humans either to fall into the lowest of the low as a result of being overcome by their corporeality, or to rise to human perfection and the highest of the high by God's help and permission, through acting around the orbit of Islamic thought, belief, and awareness. Thus, what we call "spiritual journeying" is one of the significant ways of advancing toward and reaching the Ultimate Truth, and being a perfect human being through this tide.
All these tides, continuous mutual influences and flows, and journeys occur on the steed or ship or spacecraft of the human soul. The compass of this apparently abased vessel is belief, the path or direction it must follow is Islam, and its captain or guide is the Prophet Muhammad, the Master of creation, upon him be peace and blessings, and the dynamics to advance along this path are provided by reflection and remembrance of God. However, there are some apparently harmful characteristics incorporated in the nature of this steed for certain purposes. If the soul has not been purified of these characteristics and refined, it is inevitable that the meanings, conceptions, pieces of information, knowledge of God, and remembrances, and reflections that travel between the spirit and the soul suffer from some turbulence and even serious falls along the way. Such turbulence and falls should not be viewed as occurrences independent of certain other factors that originate in humans themselves. Sometimes sins, heedlessness, and carelessness cause them; sometimes temporary "whirlpools of contraction" or "spasms" interfere with the working of the rudder or the compass; sometimes direction is lost due to certain carnal amusements and relaxations; and sometimes they happen because of our unawareness that certain actions are contrary to the manner of traveling along the way, and our feeling proud of the good deeds done. If travelers view such things as viruses that can cause the demise of the spirit, and remain distant from them, and if they display serious endeavors to be purified of them under the shower of repentance, penitence, and contrition when accidentally exposed to them, then God will replace their evil deeds with virtuous ones(25: 70). That is, He will change their faculties which enable evil deeds into enablers of virtuous deeds.
Despite its satanic characteristics such as haughtiness, arrogance, egotism, jealousy, injustice, and enmity, all of which break the wings of the spirit, the soul has a fundamental potential so important and valuable that it raises it to companionship of the spirit. Provided it grasps that its essential function, as required by its position, is to become a unit of measurement to recognize God—thereby abandoning arrogance and the accompanying self-assertive, self-aggrandizing claims; so long as it turns to God in worship and prayer and seeks refuge in Him from the potential evils in its nature, following the heart and the spirit on the way to reaching God, then the soul can advance to the highest of the high on the way together with its companions, namely the heart and the spirit.
Indeed, the soul is also of great importance for humans to maintain a metaphysical tension. It (the soul) is like a mainspring allowing them to rise from being only potentially human to true humanity. This continuously keeps them busy, without allowing them to have a rest. It ceaselessly sharpens the resolution of people to struggle against its negative characteristics, and causes those who have brains to frequently beat their brains out. When, finally, human nature is matured to the degree intended for its creation, the soul becomes a slave of the king of human existence—the heart—and adopts an attitude that is capable of feeling the need to warn it from time to time, saying, "Do not be proud, O my king! There is God, Who is greater than you!" You can call the soul which has reached this point of maturity after having gone through the filters of purification "the soul refined and grown in purity," as stated in the following verses: And (by) the human soul and that (All-Knowing, All-Powerful, and All-Wise One) Who has formed it to perfection; and Who has inspired it with the conscience of what is wrong and bad for it, and what is right and good for it. He is indeed prosperous who has grown it in purity (91: 7-9).
Whatever you call it, the purified soul is the double of the spirit, continuously trying to keep away from evil, and always advancing toward good until it finally comes to a point where it abandons its basic mission—that is, being a powerful mechanism with negative aspects for human self- purification and perfection—to the nerves, extreme sensitivity, and other human temperaments. It begins to spend the remaining part of its life in the company and service of the spirit.
We have tried to explain in detail the stages of this journeying of the soul, which the Sufis experience in their spiritual journeying, under the titles of the Carnal, Evil-Commanding Soul, the Self-Condemning or Self-Accusing Soul, the Soul Receiving Inspiration, the Soul at Rest, the Soul Well-Pleased (with God, with however God treats it), the Soul Pleasing (to God), and the Perfected Soul, or the Purified or Innocent Soul. As the soul passes through these stages upward, the veils of darkness that veil human nature are torn apart one after the other. According to the degree of each, the rays of spirituality begin to shine on all sides of a human being, and an initiate or traveler thinks that they are floating in the elevated horizons of the inner, immaterial dimensions of existence.
Each of the stages mentioned above has a gift, pleasure, horizon, manner of expressiveness, and perception particular to itself. Sometimes the guide tells initiates at which stage they are, and sometimes sensitive, self-supervising initiates who are aware of themselves and lend an ear to the voice of their spirits are informed of their stage in a special way.
Even though the soul is mainly characterized by always commanding evil, when it undergoes an effective process of purification and is directed to obedience to its Lord, it can be transformed into a source of bright light, like the full moon receiving light from the sun. If, on the other hand, it is not purified, the fog and smoke of the lusts invade its horizon, and it suffers corruption under the influence of carnal thoughts and considerations, becoming so blind as not to be able to see into the transcendent dimension of existence. Then, the soul cannot continue its companionship with the spirit and becomes a marsh of evil in human nature, in conformity with the aspects of its nature, which is open to evil. Making use of certain weak spots in its owner, the soul attacks him from many fronts, and—may God preserve us—can knock him down with a single blow. The continuous request for forgiveness from God and prayer are important defenses against such attacks; the disciplines which have an important place in the spiritual journeying are a petition presented for Divine protection, and following the way of God's Messenger, upon him be peace and blessings, strictly offers a reliable refuge. Further, restricting our consumption to absolutely essential human needs, silencing the soul by being content with legitimate pleasures, and incessantly warning the soul against illicit desires and appetites form another way of keeping it under strict control.
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Basically, the soul is one of the faculties with which humans have been equipped. Provided that humans employ these faculties, which have been entrusted to them in their creation, in the direction established by their Creator, they greatly add to their value. For example, the eyes are windows for seeing things within their scope of sight; the ears are receptors and transmitters that receive and conduct sounds and voices at certain wavelengths to the brain; the tongue is an inspector of innumerable tastes, and the translator of thoughts and feelings. If the eyes are used to see things which are religiously permissible to observe, if the ears are kept closed to harmful, evil sounds and voices while transmitting the good ones, and if the tongue stirs up feelings of reflection on and thankfulness to the numberless bounties bestowed by God Almighty, and also acts in conformity with the Divine purpose for its creation as a means of speech—then individually and collectively these organs become wings for human beings to rise to human perfection. But if, on the contrary, the eyes busy themselves with those things that the Religion condemns as harmful or ugly, thus abandoning themselves to contamination; if the ears work like a telephone exchange for vices, receiving and transmitting that which is religiously forbidden; and if the tongue lives in attachment to the tastes it recognizes, in oblivion of its duty of inspection, and speaks without recognizing any criteria—then the wings of the heart are broken, and the spirit becomes as if nitric acid were poured into its eyes.
The soul is no different from the faculties mentioned above with respect to its duties and its fulfilling or not fulfilling them properly. If the soul is purified and preserved against working like a telephone exchange for Satan, then while being, by its primordial nature, a reptile- like creature crawling on the ground, it becomes like a dove flying over our heads, as if it has undergone a mysterious metamorphosis, and it is praised by the words of God Almighty: I swear by the self-accusing soul (75: 2). When it takes two steps further, it is honored with the breezes of appreciation: O, you soul at rest! Return to your Lord, wellpleased (with Him and His treatment of you), and well-pleasing to Him (89: 27-28), and establishes itself comfortably next to the spirit.
Thus, this hard-natured substance, more harmful than snakes and scorpions, which is described by the Divine statement as Surely the carnal, evil-commanding soul always and insistently commands evil (12: 53)—by asking God for forgiveness in awareness of its sins, by avoiding its faults due to repugnance, by trying to keep distant from unbelief, hypocrisy, vice, and transgression, by shuddering with fear that the favors coming when it is in an agreeable state may be a means of perdition, and, in a further attempt, by finding its true purification through always seeing itself as impure, this primordially hard-natured, evil-commanding substance can rise to great heights and approach the heavenly beings. The soul at this level, which philosophers call "the speaking self or soul," and which the Qur'an describes as "the soul at rest," has become such an earthly being able to rise to the horizon of the heart and the spirit and possessing angelic manners, that it begins to take pleasure in religious responsibilities, which previously it did not like and which were difficult for it to fulfill. The things which it found bitter up until this point have become sweet, and in parallel with its attaining this station, the cloud of dust and smoke over the spiritual intellect and the secret that was produced by corporeality has been completely removed. Things and events appear differently to its view, and time and again it experiences raptures with the call to Him it hears from every thing and event, thinking itself to be among the pure spirit beings in great joy.
A time comes when reason becomes like the heart, and its products take on the color of those of the spiritual intellect. An initiate with such a level of reason feels stunned by awe of God and advances full of the feeling of modesty; he sometimes becomes exhilarated with the showers of Divine gifts. The heart beats "God! God!", combining this with the breaths of reason that utter, "O the All- Forgiving! O the All-Veiling (of His servants' sins and shortcomings)!" The initiates at this level of reason hear the whole of creation mentioning God by His Names, and their breaths resound with Him. While, on the one hand, signals come to them from the horizon of the spiritual intellect, arousing them to the worlds beyond, on the other hand they feel great worry that the gifts may be interrupted and unexpected obstacles may come in between them and the Source of these gifts, causing them to turn to Him more frequently and more intimately, admitting that whatever good visits them is essentially from Him.
The zeal they feel is the zeal of the heart, and the sorrows they suffer are the sorrows of the sincerely penitent ones. While looking at their past with repugnance, they are revived and refreshed with the hope of a brighter future and the hope that they will be able to compensate for their past defects with future opportunities. They try to fill their past voids with heartfelt sighs and groans and with reflection and remembrance. While others are busy with a life of ease, thinking that they have already lived so before, they always try to do whatever they must on the way to God.
Such people always feel themselves to be in the presence of the Lord. They stand before Him in awe, bow before Him in utmost modesty, prostrate before Him with utmost humility, and sit before Him in self-supervision. They advance with utmost awe and care, and try to fulfill what is required by having reason in the company of the heart. They shudder with awe while thinking of Him, they breathe His mercy with reflection and remembrance of Him; they focus their observations on deepening their knowledge of Him with new discoveries, and their eyes twinkle with eagerness for reunion with the All-Beloved. They do not forget their defects, which are incompatible with servanthood to God, seeing them as precipices between them and their Lord; they entreat Him, saying, "Do not abandon me to myself, even for the blink of an eye!"
Now they have distanced themselves from Satan, but they also reinforce the barriers they have put before Satan's inlets into their heart and continue to erect new ones. Whenever they remember Satan, they feel as if they are in the valley of bandits, and they always seek refuge in God, saying, "I seek refuge in You from the promptings and provocations of the satans; I seek refuge in You, my Lord, lest they be present with me!" (23: 97–98).
They never rely on themselves, their labor, or their deeds; they do not approve of their acts, and treat them with disdain. They are always troubled and shake like a tree in a storm with the worry that hypocrisy and expectation of others' acceptance and appreciation have found, and do find, a way into even their best deeds. These considerations follow them ceaselessly along the way, until finally the soul is welcomed with the compliments, "O you soul at rest! Return to your Lord, well-pleased (with Him and His treatment of you), and well-pleasing to Him! Enter, then, among My servants (fully content with servanthood to Me)! And enter My Paradise!" (89: 27–30); while those who have dropped halfway groan with deep regrets, "Would that I had forwarded (some good deeds) for my life (to come)!" (89: 24). They are honored with surprising bounties of the Hereafter, and favored with many different gifts from the horizon of the heart.
They are treated thus because they have lived a life of austerity without being deceived by worldly pleasures, and they have advanced toward the horizon of the peace of the heart, spiritual contentment, and resignation to God's treatment of them. They felt obliged to advance so, conscious of their essential impotence and poverty and their absolute need of Him. They have advanced and been favored with His special wealth. They have heard many things which other ears could not hear, and seen many things which other eyes could not see; they have experienced how the most honored of creatures—humanity—was created from wet clay, how matter rose almost to the level of the spirit, and how the evil-commanding soul developed into the soul at rest. With the pleasureof watching the smiling face of their fate, they have proceeded beyond space within space and toward the All-Beloved within corporeality, to the point where the invisible becomes visible.
The exacting people of truth and wisdom have seen the soul as we have so far tried to explain. If the Master of all domains had willed it to be so, there is none who could have willed or done otherwise. If He has dressed non- existence in the array of existence, why then should we wonder at "nothing" being "everything"? If He wills, He can make a drop into a sea, a minute particle into the sun, manifest thousands of instances of existence in non- existence, and bestow kingdoms upon those who initially have no trace of one.
O my God! Surely I ask You for a soul content with You, believing in meeting You, resigned to Your decrees, and content with Your bounties. And bestow blessings and peace on the most perfect and complete of the spirits, who is our master Muhammad, and Your beloved, and on His Family and Companions, whom You love!
 See M. Fethullah Gülen, Emerald Hills of the Heart – Key Concepts in the Practice of Sufism, The Light, NJ, 2004, vol. 2, pp. 251–261. (Tr.)