A wise man once said: "Faith is to believe there is an ocean, because I saw a stream."
The Credo (the Latin word meaning "I believe") has been the expression of Christian belief from the outset. As a result of Saint Paul’s missionary journeys, the early Christian communities felt the need to express in concise words their fundamental beliefs. These formulations are known as creeds.
The first to be widely used is called The Apostles' Creed, signifying the direct link to the Twelve whom Jesus chose as companions. This is the creed that is most often used at Sunday Mass. Another one was later formulated during the 4th century, the Nicene-Constantinopolitan. This creed was the work of two councils, held to deal with numerous theological debates about Christ that were causing division among believers. (A Church council is convened so bishops, together with the pope, can debate issues crucial to the Universal Church.)
Be it The Apostles' Creed or The Nicene-Constantinopolitan Creed, the Credo has a Trinitarian structure (see the article on the Trinity). The first part, very short, introduces the Father; while the second, the longest, relates to the Son. The last section is about the Holy Spirit and the Church.
The Credo is the response of the baptized to the three questions, which begin with “Do you believe?”, that the priest or deacon asks during the baptismal ceremony.
Why such an affirmation of our Christian faith? To understand better that which we believe, to proclaim it to all who thirst for the truth, and finally, to unite as one body the different Churches who profess the name of Christ.