Qabd (contraction) and bast (openness), felt by almost every-one during their lives, relate especially to those who live their lives consciously. Literally meaning being caught, being in straits or distressed, and being grasped by hand, Sufis use qabd to mean that the link between an individual and the source of his or her spiritual gifts and radiance has been severed for a certain period.
This causes distress and makes one suffer from spiritual obstruction and blockage. On the other hand, bast can be described as openness, expansion, development, relief, and being freed from spiritual blockage, and as developing inwardly or spiritually to the point that the seeker becomes a means of mercy and embraces all things or beings in existence.
Fear and hope or expectation are deliberate attitudes, and are a first station for a traveler on the way to God. Contraction and openness are mysterious "bargains" that have been made without the will or intention of the traveler. The first one blocks his or her way; the second one gives him or her wings to fly to the heights. If fear and hope represent anxiety about and the joy of expectations for the future, as well as liked and disliked things, contraction and openness can be regarded as the heart's contracting with gloom and depression and expanding with joy.
Contraction and openness have the same meaning for travelers on the slopes of knowledge of God as do fear and hope or expectation for the newly initiated. Both are in the hands of God, even if we cannot exclude from them part of one's free will: God contracts and expands (2:245). As the whole of existence is in His grasp and at His free disposal, it is He Who directs and disposes of all things, from the heavens to the human heart. The Prophetic saying: The heart is between the two Fingers of the All-Merciful; He turns it from state to state and gives it whatever form He wishes reminds us of this fact. 
When God wills, He contracts a heart so tightly for what only He can provide that only He can satisfy it. By contrast, He expands and exhilarates it to such an extent that it needs nothing. Contraction is caused by God's Majesty; openness is caused by His Grace. While Grandeur and Magnificence relating to God's manifesting all of His Names on the whole of existence are displayed in the former, Mercy and Condescension are manifested in the latter. In the former, there is the frightening, awesome, and majestic nature of the Power that turns all existence from huge systems into particles, while in the latter there are affectionate breezes for those spirits trembling in awe of this infinitely vast, overwhelming Power, this overpowering Majesty.
Not everyone can feel such manifestations of Majesty and Grace at the same level, for the extent of contraction and openness is proportionate to one's emotional and spiritual capacity. What an ordinary person feels as distress and relief or rejoicing differs markedly from the spiritual joy and anxiety experienced by one awakened to Divine truths, one who is ever-alert for what will come through the half-opened door from the realms beyond, and conscious of God's continuous and direct supervision.
Like every element of existence, contraction and openness are at the disposal of the Creator, Who alternates them continuously like night and day. Even if this alternation appears to originate in one's deeds done in accordance with one's free will, the Divine Will extends or shortens the periods of contraction and openness, and causes one to be consumed with tension or to overflow with delight. Sometimes a lover experiences a long span of time as if flying like a bird without being touched by any form of contraction; other times contraction is a constant companion that stays so long that the lover feels that he or she is going from one hardship to another (and greater) hardship.
As neglecting the requirements of one's spiritual position bestowed by God causes contraction, sins usually come together with contraction. For this reason, a believer must always be alert (against committing new sins and deviations) while suffering contraction, must not be overpowered by heedlessness, and must strive for self-purification through sincere repentance and per-forming good deeds. Then, the believer must wait for what will come from the realms beyond.
While contraction is accompanied by fear, perplexity, and feelings of spiritual emptiness, openness manifests itself as joy, rapture, and feelings or utterances of pride. For this reason, openness may be risky for those spiritually less-developed people who have not yet attuned themselves to journeying in "celestial" realms.
Although there are risks associated with contraction, those associated with openness are greater and more numerous. One caught in contraction usually feels in his or her conscience an absolute need of the Almighty, and so turns to Him in sincere acknowledgment of this neediness with the words: Hold me! Hold me, lest I should fall! and, escaping the spiritual waste he or she feels, is favored with the Almighty's help and reaches those heights that are beyond reach during times of openness.
This is why some people are exposed to heedlessness and loss of spiritual energy during times of openness, and why contraction leads almost every believer to new levels of alertness. In addition, the contraction originating from our sins or neglect usually signals the beginning of a new wave of openness; similarly, an expansion that causes pride and loss of spiritual energy may give rise to a new contraction.
A true believer is one who can judge each state experienced or achieved as it really is, with all of its aspects, and make it fruitful. Contraction and openness are manifestations from Him for one who knows. He causes openness so that the servant will thank Him, and causes contraction so that the servant may become more alert.
 Ibn Hanbal, Musnad, 2:173; Al-Tabari, Jami' al Bayan, 3:126.