In Book IV of Milton's Biblical epic Paradise Lost, on which this painting is based, the angels Ithuriel and Zephon are charged by Gabriel to watch over the innocent slumbers of Adam and Eve in Paradise. But the hordes of Satan were prowling around, and when the two angels came to the sleeping Eve they found Satan whispering at her ear.

Him there they found
Squat like a toad, close at the ear of Eve,
Assaying by his devilish art to reach
The organs of her fancy, and with them to forge
Illusions as he list, phantasms and dreams.

Him thus intent Ithuriel with his spear
Touched lightly; for no falsehood can endure
Touch of celestial temper, but returns Of force to its own likeness. Up he starts,
Discovered and surprised.
- Milton

After being expelled from the Garden of Eden, In the beginning humans in nature needed food, then came the spear & humans ate. They fished and hunted using sticks, then built spears, thus the Spear is the first weapon ever built for mankinds survival and is the most sacred of all weapons to mankind.

Spears are one of the earliest and most important tools developed by early humans. As a weapon, spears were either designed to be used in melee, or to be thrown, it may be wielded with either one or two hands. It was used in virtually every conflict up until the modern era, where even then it continues on in the form of the fixed bayonet, and is probably the most commonly used weapon in history.

Archaeological evidence found in present-day Germany documents that wooden spears were used for hunting since at least 400,000 years ago, and a study suggests that the technology of hafted stone-tipped spears found in Africa date back to about 500,000 years ago. There have also been suggestions that the discovery of spear use could perhaps even been traced back to five million years ago.

Native American spears were an extremely important part of the daily lives of Native American tribes for centuries. They were used for hunting and later for warfare as well. Native American Indian spears are hand crafted and often could reveal a status among individuals within a tribe. Usually made of wood, the shafts of most Native American Indian spears were made of wood, and the tips made of various materials like bone spear tips, flint spear tips, obsidian spear heads, wood spear heads and eventually metal spear heads after the introduction from the Europeans.

Like many weapons, a spear may also be a symbol of power. In classical Greek mythology Zeus' bolts of lightning may be interpreted as a symbolic spear.

The trident (which is a triple spear) is the weapon of Poseidon, or Neptune, the God of the Sea in classical mythology. The trident may occasionally be held by other marine divinities such as Tritons in classical art, and trident maybe depicted in medieval heraldry as well, sometimes held by a merman-Triton.

In Hinduism, it is the weapon of Shiva, known as trishula (Sanskrit for "triple-spear") and considered a divine symbol, commonly used as one of the principal symbols in Hinduism. When looked upon as a weapon of Shiva, the trishula is said to destroy the three worlds: the physical world, the world of the forefathers (representing culture drawn from the past) and the world of the mind (representing the processes of sensing and acting). The three worlds are supposed to be destroyed by Shiva into a single non-dual plane of existence, that is bliss alone.

The three points have various meanings and significance, and, common to the Hindu religion, have many stories behind them. They are commonly said to represent various trinities—creation, maintenance, and destruction; past, present, and future; body, mind and atman; dharma or dhamma (law and order), bliss/mutual enjoyment and emanation/created bodies; compassion, joy and love; spiritual, psychic and relative; happiness, comfort and boredom; pride, repute and egotism; clarity, knowledge and wisdom; heaven, mind and earth; soul, fire and earth; soul, passion and embodied-soul; logic, passion and faith; prayer, manifestation and sublime; insight, serenity and Bodhisattvahood or Arhatship (anti-conceit); practice, understanding and wisdom; death, ascension and resurrection; creation, order and destruction; the three gunas.

The spear is also used by certain wandering Sufi ascetics, as depicted by this Palestinian dervish. An intense practice and brand of Sufism in Islam involves ascetics stabbing themselves with spears without being hurt or any bleeding. The ritual is usually accompanied by Zikr ("Chanting") and dates back to the early days of Sufism and is performed as both a display of a practitioners spiritual superiority over this worlds matter and the illusions of this world and is also a means of recruiting new members by proving God’s existence through a demonstration of his miraculous healing powers.

Other spears of religious significance are the Holy Lance and the Lúin of Celtchar, believed by Christians to have vast mystical powers. The Holy Lance, also known as the Lance of Longinus (named after Saint Longinus), the Spear of Destiny, or the Holy Spear, is legendarily known as the lance that pierced the side of Jesus as he hung on the cross during his crucifixion.

The Persian Spear ("Neyzeh") was a thrusting weapon used by Ancient Persian infantry. It was the Mid-range weapon of the Persian Immortals. The spear was the Immortals primary weapon. The weapon was usually used one-handed in an overhand fashion, accompanied by a shield; although it could be used two-handed. The round counterbalance could also be used as a bludgeoning weapon.

One of the key advantages of the Persian spear was that Persian Immortals were trained on its use both as infantry and cavalry. A longer variation of this spear was used by a high ranking Immortals whom were the royal bodyguards and so the most elite members of the army.

It was also used by the demon headed Persian warriors called (Deevsaran) leaving an ever-lasting imprint on the human psyche as Spears being a tool of the devil usually symbolized by the pitched fork of satan or the devil himself.

Satan has also been depicted with a trident spear.

Satan with pitchfork in hand is usually seen herding souls away from God, harvesting & farming corralling souls off to a firey hell to the blast of a demon's trumpet like some parade in our worst nightmare, eating the souls cut up by the Sword and Word of God with it (like a fork) and tormenting the souls of the damned. It also represents the devils claw.