Pentagram (large version)

Many Neopagans, especially Wiccans, use the pentagram as a symbol of faith similar to the Christian cross or the Jewish Star of David. It is not, however, a universal symbol for Neopaganism. Its religious symbolism is commonly explained by reference to the neo-Pythagorean understanding that the five vertices of the pentagram represent the four elements with the addition of Spirit as the uppermost point. The outer circle of the circumscribed pentagram is sometimes interpreted as binding the elements together or bringing them into harmony.

See also:
https://www.cafepress.com/pentagramgreen2