1.  Sleep symbolizes death just as being awake symbolizes life (Psa 13:3; Jer 51:39; Dan 12:2; Jn 11:11-13; 1 Cor 11:30; 15:51). God created sleep to remind man of death for the Appeal Trial of Satan as an extension of the Prehistoric Angelic Conflict.  Sleep also symbolizes the rest of Spiritual Maturity ((Heb 4:3) and peace (Psa 4:8; Gal 5:22).  Sleep includes rest, relaxation, and peace.  And married people sleep together in a time of bonding and togetherness (SOS 1:13; 3:1; Heb 13:4).
 

2.  Sleep is associated with darkness, which is the realm of Satan and his demons (Acts 26:18; 1 Thess 5:7).  Demons and the creatures of darkness, like owls, frogs, and varmints, come out at night.
 

Five distinct sleep stages, or levels, have been identified.  The first stage is light sleep as the person falls asleep, while the fourth stage is the deepest.  Awaking from the fourth stage leaves a person groggy and disoriented.  During the first stage, the state between sleep and wakefulness is called the hypnagogic state.  In the hypnagogic state between sleep and wakefulness a person is susceptible to demon influence.  The hypnagogic state often occurs about 30 minutes into the sleep cycle.  Being awakened sharply about 30 minutes after beginning to sleep is usually due to a demon.  As the person is  waking, the demon may be visible in some form of light display or image with the eyes closed or open.
 

The fifth stage of sleep, called the Rapid Eye Movement (REM) stage, replaces stage 1 as the sleep cycle rolls back up from deep sleep.  In the REM stage dreams occur.  In the REM stage of sleep, the person may be paralyzed, which serves the useful purpose of preventing him from acting out his dreams.  Dreams can be interpreted in Grace from divine viewpoint of their symbols, whether the dreams are caused by angels, demons or soulish response (Gen 37:9-10; 41; Judg 17:13-15; Dan 2; Matt 1:20; 2:12-13, 19, 22).  Dream symbols, however, do not always have the same meaning as the same symbols on the Stage of Life during the day.  Although God does not speak to people through dreams in the Church Age, dreams may reveal spiritual issues or personal problems.
 

Hypnotic pressure from Satan, demons, or angels can cause one to fall asleep (Isa 29:10; Dan 8:18; Matt 26:40-45).  A person in the presence of a powerful angel or demon may be overcome with pressure and faint in the soul or fall asleep like a person under hypnotic power.
 

The Lord watches over a person and protects him in sleep (Psa 127:2).  Elect Angels may also guard a person during sleep (1 Ki 19:4-8).  An Elect Angel came to assist Elijah when he was in a crisis fleeing from Jezebel.  However, the night belongs to Satan, and he is allowed to cross examine even during sleep.  He didn't leave Job during the night.  A good night's sleep is a blessing (Job 11:18-19; Prov 3:24; 19:23; Jer 31:26), but sleep deprivation is a form of torture.  It may be caused by demons, who don't sleep.  Anxiety, which prevents sleep, may be caused by a demon.  The solution is to resist the demon, and he will flee (James 4:7).  Failure to handle problems during the day can leave garbage in the subconscious, which comes out at night and causes bad dreams or anxieties that interfere with sleep (Esther 6:1; Dan 2:1; 6:18; Matt 27:19).

Too much sleep is a form of idleness that interferes with industriousness (Prov 6:9-11; 19:15; 20:13).  No work is done when a person is sleeping.  Exercise helps sleep (Eccl 5:12).  Even exercise early in the day contributes to a good night's sleep.
 

Since sleep is a form of self-love, it is an indicator of self-esteem (Eph 5:28-29).  If a person sleeps eight hours a night, that is a third of the day and a large portion of a person's life.  Such a large investment reveals a person's true nature and priorities.
 

Nightmares may be caused by demons or Elect Angels (Job 4:13-21).  Nightmares and traumatic dreams are warnings that should not be taken lightly.  They may be warnings of an approaching crisis or signs of psychological or physical danger.  Rather than dismissing a child's nightmares, the underlying spiritual meaning should be sought.

Maladies

A good night's sleep is necessary for mental alertness and physical strength during the day.  There may be problems sleeping at night or problems staying awake during the day.  Lack of sleep at night and sleepiness during the day are both problems.  The proper balance of sleep and wakefulness must be maintained.  However, the pressures of life inevitably interfere with that balance.

Sleep problems are personal problems that can be handled with the Problem Solving Devices of the Spiritual Life.  Since God normally provides good sleep (Ps 127:2), sleep problems are symptoms of problems in the Spiritual life.  Sleeplessness may be the sign of a crisis (Esther 6:1; Dan 2:1; 6:18; Matt 27:19).  Anxiety may be handled by Rebound and Faith-Rest (1 Pet 5:7), but it may also be due to a demon attack.

Sleepiness may be caused by lack of capacity for life, alertness, and objectivity due to laziness (Prov 6:9-10), Cosmic System pressure (Matt 26:40-41; Acts 20:9),  demon influence, or pressure from an Elect Angel (Dan 10:9).  Some demons, like the kosmokrator, world ruler, (Eph 6:12), drag people into hypnagogic or hypnotic states.

Psychological Disorders

Psychological disorders and mental illnesses are usually accompanied by sleep problems.  That is because of demon attacks in addition to stress.  Sleep in the Bible may refer to spiritual death, physical death, or reversionism.  Psychological disorders come from reversionism.  "Sleeping ones" may refer to those who are not saved or not alert and not living the New Spiritual Life (ref. Eph 5:14).

Dreams

Bad dreams and nightmares may interfere with sleep.  These dreams are usually caused by a demon who specializes in such dreams, although they can also be caused by an Elect Angel (Job 4:13-21; Dan 2:1).  The demon comes through relationship with another person who has the demon.