How long does a prayer of liberation or exorcism last?

The answer is difficult to give. There is no single easy answer. It can be as short as 30 minutes to as long as four hours or more. It can be one session but most of the time multiple sessions. It really all depends on many factors. Nonetheless, two things need to be considered:

• What is the cause of the attack?
• How deep is the cause, i.e. how embedded is it in the soul?

Why the need for multiple exorcisms?

Often when a person asks to be liberated, the assault has already advanced to a level of either oppression or possession. This is now an advanced stage, and the psychic abilities are well developed and the control of the spirit of divination over this ability is often total and very well pronounced. It has arrived to such a degree because the person has taken advantage of the power being given by the spirit of divination and has enjoyed or benefited from its use for quite some time.

Moreover, the longer the time that has lapsed from the moment of contamination to the time of seeking for divine assistance, the more difficult it becomes, the longer the needed time for spiritual liberation. For in many ways, other sins become involved in the life of the person. And grave sins like idolatry, sexual immoralities, uncontrolled passions, occult practices and beliefs would invite other nefarious spirits in the life of the person.

Once the person becomes aware or have been enlightened that the source of the power is evil and desires to be rid of it and the demon, then retaliation sets in. This is manifested by psychic and physical attacks on the afflicted for any intention or act to pray to God and ask for divine help. The difficulty is also exacerbated because the demon now uses other people, usually also those with open occult third eye, to dissuade the afflicted from seeking the help of the Church and her ministers especially the exorcists. They would instead, recommend that the afflicted use amulets or talismans for protection, or do some occult ritual, or to consult a local occult healer (shaman or albularyo). This of course would even more fortify the demonic stronghold on the person by inviting other demons, thereby, making spiritual liberation difficult.

Take for example the demon of greed for power and lust called Asmodeus. It is often found bundled up with the demon of Gluttony (Beelzebub) and Avarice (Mammon). These are the demons of worldly pleasure and the demon of divination would invite them as the person who possess the power of divination would often times also be attracted to pleasures of the stomach, pleasures of the flesh, and pleasures of wealth.

Artist's conception of the demon Asmodeus
http://www.smilingdemon.com/PANDEMONIUM/92-DEMON_ASMODAY.htm

Looking at the artist's conception of Asmodeus, one sees how incisive they are in a person's life. This demon would penetrate every area of the soul, the mind, the emotions such that it would control it completely. Multiply this thought with other demons present in a person. Then one can have an idea of the battle one is up against when desiring to be truly free from them.

In the absence of sanctifying grace in the soul, the unclean spirits latch on the person both on the level of the soul (for those in a habitually sinful life) and that of the level of emotions and its passions (connected with pride, vainglory, sloth, avarice, lust, anger, resentment, and unforgiveness, etc.). It is not rare that demons would also latch on the body, bringing in infirmity. Therefore, in effect we are no longer dealing here with just one spirit, which originally was the spirit of divination, but already many spirits. It is for this reason that a series of exorcism prayers will be necessary.

The need for conversion

It is necessary for the expulsion of demons that the afflicted seek the divine help with sincerity, in a spirit of total surrender, and humility. The afflicted must prepare spiritually weeks before the prayer intercession. The person must obey all the spiritual assignments given by the exorcist, which must include –honest and sincere repentance of all sins and serious amendment of life. This must be expressed through regular sacramental confession; daily examination of conscience, reverently going to Holy Mass and receiving Holy Communion in a proper disposition; development of lively spiritual life of prayer, mortifications, penance, charitable and virtuous life. The afflicted must strive to live in habitual sanctifying grace. Total consecration to the Lord Jesus Christ, manifested in a loving and trusting relationship with Him must precede any spiritual liberation prayers. These are necessary to loosen the hold of the evil spirits in the person. Without proper spiritual preparation and perseverance on the part of the afflicted, the battle would be tortuous and healing long in coming. Thus a person in a habitual state of sin must now be replaced by habitual state of grace. The absence of true conversion on the part of the afflicted would prevent healing. It is then a waste of time and energy for the exorcist and the afflicted.