The Element Encyclopedia of Witchcraft: The Complete A-Z for the Entire Magical World - Judika Illes 2005
Sigils are also known as seals. They are specific geometric or visual designs usually enclosed in a circle and are used for various magical and spiritual purposes.
Commanding and Compelling makes much use of sigils: each spirit, whether angel or demon, is believed to possess a specific sigil. Allegedly if the sigil is created perfectly, the spirit must answer its summons.
Traditions similar to sigils exist round the world. Although the designs are unique, purposes and concepts are closely related.
In Vodou, each lwa possesses a veve, which may be used to beckon (although never command; this is a far more respectful tradition) their presence. Veve designs may be carved onto candles similarly to sigils or used for meditation, however they are most frequently drawn on the ground by sprinkling corn meal or other powder.
Sigils are also used for various magical purposes. Seals are incorporated into candle magic and are used to create protective talismans. Sigils can also be used to create personal defensive shields.
Pennsylvania Dutch hex signs are another form of sigil. Hex signs are often considered nothing more than Pennsylvania Dutch folk art, however they are actually magical signs and sigils. They are most commonly found painted onto building façades or gable ends of barns. Designs have historically also been included on furniture, documents, tombstones, pottery and ceramics, and written amulets.
Hex sign literally means “witch sign.” Hex signs are also known as hexafoos or “witch foot.”
Their origins are mysterious. Jakob Grimm and other scholars recognized the geometric patterns as deriving from pre-Christian spiritual and magical traditions. They were first used in medieval Germany and Switzerland and may be based on runes. Another school of thought, however, insists that hex signs are nothing more than aesthetically pleasing adornment.
Hex signs consist of simple and colorful geometric designs that require relatively little artistry. If you can draw a straight line, you can draw a simple hex sign, although perhaps not the most elaborate ones. Different hex signs have different names, meanings and powers—for instance to keep lightning or hail from striking or to prevent animals from becoming ferhexed (bewitched). Explanations dating back to the 1920s, especially those geared to tourists, suggest that hex signs are decorations intended to ward off malevolent witchcraft or evil influences including the devil—in other words, they are sigils.