The peacock was believed by the ancients to have flesh that does not decay after death, and thus became a symbol of immortality. This symbolism was adopted into Christianity, and the peacock appears in many early Christian mosaics and paintings to represent eternal life.
The peacock is used in church decorations in the Easter season, which celebrates the Resurrection of Christ and eternal life.
Alternatively, because of the way a peacock struts and displays its feathers, the peacock is sometimes used as a symbol of human vanity.
Sources
- "birds, symbolic." Peter and Linda Murray, Oxford Dictionary of Christian Art (2004).
- Patricia S. Klein, Worship Without Words: The Signs and Symbols of Our Faith (2000).
- Symbols in Christian Art and Architecture by Walter E. Gast.