This is part of a ritual done at the Covenstead by a High Priestess in the tradition – on the North wall there is the symbol of the Pentagram flanked by two wall scones. 

The ritual is done on Full Moons on the nights when the Moon is seen as full – if meeting with the coven, usually before the ritual commences for the Full Moon. 

What is its purpose? It serves as a minor house-blessing with protective qualities. When you analyze the Invocation that goes with it you can see its purpose – that no evil thing, nor adverse thought-form may come through the Covenstead door. 

Photo from the Wolfa Covenstead… 

Blessed Be!