Catechism of the Catholic Church

The Greek word symbolon meant half of a broken object, for example, a seal presented as a token of recognition. The broken parts were placed together to verify the bearer's identity. The symbol of faith, then, is a sign of recognition and communion between believers. Symbolon also means a gathering, collection, or summary. A symbol of faith is a summary of the principal truths of the faith and therefore serves as the first and fundamental point of reference for catechesis.