There is power in meanings of the old images and symbols. Below is a compendium of common symbols, charms and totems from antiquity that are thought to be useful against psychic aggression:

Abracabadra: One of the oldest protective amulets, this is the word Abracabadra written in a triangular form like as below for Protection:

A
AB
ABR
ABRA
ABRAC
ABRACA
ABRACAD
ABRACADA
ABRACADAB
ABRACADABR
ABRACADABRA

Or written as follows with an enemys name on the reverse in order to diminish their power.

ABRACADABRA
ABRACADABR
ABRACADAB
ABRACADA
ABRACAD
ABRACA
ABRAC
ABRA
ABR
AB
A

This talisman is thought to protect against injustice and evil events.

Agrippas Pentagram: A five pointed star superimposed like figure of a Male with arms and legs outstretched. It is used to increase connection with the Higher Self as well as to protect against both visible and invisible astral attackers.

Bast: This is usually represented by the image of a black cat. In ancient Eygpt, Bast or Bastet was thought to protect home and family from negative spiritual influences.

Cancer: The astrological symbol of Cancer, the Crab is thought to protect against astral attack.

Celtic Knots: These rings of circles created from interwoven bands appear in all kinds of intricate forms and designs. One of their prime functions is to protect against wicked plots, group magic, evil spirits and demons.

Celtic Cross: A crucifix within a circle,this ancient symbol is thought to protect from spiritual dangers of all kinds.

Devils Snare/Trap: This is a circle of Hebriac writing that spirals inward in a counterclockwise direction. The idea is that evil spirits become trapped in the coil of writing. It is Assyrian in origin and thought to protect against sorcery and all evil.

The Dog: A North American Indian talisman against astral attacks. He stands at the doors of the otherworld and prevents spirits from attacking the living.

The Elk: A symbol of psychic self defense and protection, the rune of the Elk (Algiz) is worn to defend against spirits and make one brave while facing fear of the unknown.

Eye of Horus: An important protective symbol in ancient Egypt it helps protect against the evil eye.

Eye in the Triangle: This is usually a pendant featuring an eye in the center of a triangle. It is thought to repel the usual causes of the evil eye jealousy and envy.

The Falcon: The Falcon is a North American symbol of perception and represents the high perch of elevated spirituality. It enhances astral abilities so one is able to perceive negative energy and make it ones metaphorical prey.

Mother Gaia: This is usually the figure of a Goddess with her hands reaching in a circle above her head. She protects against disturbances to our auras and helps ground our energy

Fish: In North American Indian cultures, the fish represents a refusal to recognize the power of anothers magic.

The Frog: North American symbol indicating mediumship. It is thought to cleanse and purify the aura.

Hagal: This protective rune looks like an H, represents hail and protects from all attacks and misfortunes including astral attack.

Ingwaz: This rune resembles a diamond shape and represents an egg. It is protective against the evil eye and astral attack.

Horse: A North American Indian symbol that dissolves astral blockages and cleanses the aura.

Isa: The symbol of an I that represents Ice. It is thought to increase personal shamanic powers as well as protect one from evil influences and undesirable astral forces.

Jaguar: The Mayan symbol of the jaguar is thought to protect against control freaks, evil thought forms and increase ones own shamanistic abilities.

The Lucky Hand: There are many variations of this from all cultures, but this usually features the palm of a hand facing out. In the center of the palm may be a pentagram, an eye, a gemstone or signs of the zodiac. It is thought to protect against all forms of astral invasion and attack. It is especially effective against ritual abuse.

The Griffin: Most Griffins feature the body of a lion and the head of an eagle. Some versions have wings. This mythical being, that is Grecian in origin is said to protect the psyche from dark forces.

Mannaz: This protective Rune resembles an M and represents the higher self. It protects against the cruelty of interference with ones connection to their gut instincts and God.

The Mitzu Domo: This symbol is Japanese and features three whirling swirl shapes. It is thought to protect against the impatience, greed and acceleration of time associated with astral attacks.

The Om Symbol: This ancient Sanskrit Symbol represents the syllable om that is used in meditation. It raises ones vibration so that the aura can not be reached by the baser energies associated with psychic aggression.

The Pentagram: Also known as the Druids Foot, this five-sided star protects against witchcraft and the evil eye. It is thought to return bad energy back to the sender.

Pictish Knot: This Celtic symbol that features an interlocking series of triangles protect against magical rites that have gone wrong and missed their aim.

The Raven: A North American Indian and Celtic Symbol thought to protect against black magic.

Sagittarius: The astrological symbol of the Archer is thought to protect against psychic vampires and those who deplete spiritual energy.

Scorpio: The astrological symbol of Scorpio, the Scorpion is thought to protect against witchcraft, the evil eye and the kind of fanaticism associated with cults and ritual attack.

Seal of Solomon: One of the best known of protective symbols this features two interlocking triangles that form a star shape. It is used to invoke the Archangels and protect against black magick and the power of all evil.

The Sheiah Dog: This Celtic symbol, which features a dog within a circle was a guardian of the secrets of the Druids and Metaphysicians. He protects from black magic.

The Sun: The universal symbol of the sun is warn to oppose its shadow: dark energy of all kinds. It is common to all cultures.

Suli: This is a Celtic amulet that depicts the Sun Goddess in a halo of flames. He protects against spiritual weakness.

Thors Hammer: This symmetrical three-pronged knot protects against misfortune, the evil eye and those who would rob the spirits.

The Turtle: Helps one remain invisible to others on the astral plane.

Uruz: This Nordic Rune looks like an upside down U and represents an Ox. It helps one connect to their higher self and protects against astral attack. It is thought to help one remain grounded spiritually.

Virgo: The astrological symbol of Virgo, the Virgin, is thought to protect against cults, covens and groups that do not encourage soul freedom.

The Wolf: A Northern European and North American Indian symbol of protection against astral attack.

The Yew Tree: Increases endurance and power and is thought to protect against deception, betrayal, delusion and undesirable influences and thought forms. The rune that symbolizes the Yew Tree (Eiwaz), is worn as a protective talisman.