CROSS. Buffyverse Term/Concept/Idea/Intratext.

An object, typically consisting of a piece of wood, metal or stone with a single horizontal crossbeam, which symbolizes the death of Jesus Christ. In the Christian tradition, the cross is a symbol of both the sacrifice of Christ and the subsequent purification which results from his death and resurrection. Because of their unnatural evil, the vampires of western folklore are particularly susceptible to weapons which represent the purity of Christ.

The cross is the single most common religious symbol appearing in Buffy: Angel gives Buffy a small, silver cross in “Welcome to the Hellmouth”; the Jewish Willow nails a cross to her wall to protect herself from vampire attack in “Passion”; Giles uses a cross to keep vampires at bay in “The Wish;” Spike drapes himself over a large cross to show penance for his past wrongs in “Beneath You.” Crosses appear much more frequently in the first three seasons of Buffy than in the later four. The cross is primarily used as a secularized weapon to scare the vampires or keep them away, but it occasionally appears to represent a vague kind of goodness or purity, which, while not directly connected to the Christian tradition, is not completely separated from that tradition

--Jonathan Edwards.