"I believe in God, the Father almighty, Creator of heaven and earth, and in Jesus Christ, his only Son, our Lord, who was conceived by the Holy Spirit, born of the Virgin Mary, suffered under Pontius Pilate, was crucified, died and was buried; he descended into hell; on the third day he rose again from the dead; he ascended into heaven, and is seated at the right hand of God the Father almighty; from there he will come to judge the living and the dead. I believe in the Holy Spirit, the holy catholic Church, the communion of saints, the forgiveness of sins, the resurrection of the body, and life everlasting. Amen."
According to Church tradition, the Apostles' Creed was formulated by the 12 Apostles on the day of Pentecost. With so many people converting to the Christian faith, the Holy Spirit (who Jesus promised would guide the Apostles into all truth, John 16:13) saw it necessary that there be a common profession of the faith, or creed, to unite the Church.
According to the Catechism of the Catholic Church, the Apostles' Creed is the oldest Roman catechism and carries it's authority from the chair of the foremost apostle, Peter (CCC, 194). The Apostles' Creed is also Trinitarian, beginning with the first Person of the Trinity, God the Father, moving to the redemption of mankind through the second Person of the Trinity, Jesus Christ, and then to the work of the third Person of the Trinity, the Holy Spirit. Therefore the Apostles' Creed is also a baptismal seal: the profession of faith to which we are entrusted on the day of our baptism (CCC, 197).
The Apostles' Creed is the first prayer that we say when we begin praying the rosary. Reciting the Apostles' creed is very important because it is the profession of the Christian faith handed down from the Apostles via the Holy Spirit to the Church, and as such it is to be guarded and continually handed down to future generations.
Praying the Apostles' Creed is in itself an act of faith; it also increases and strengthens it. According to St. Thomas Aquinas, "The first thing that is necessary for every Christian is faith, without which no one is truly called a faithful Christian." The Apostles' Creed tells us the substance of our faith, that to which we are committed.
Aquinas notes that faith brings about four good effects in our lives:
1) The first is that through faith the soul is united to God, and by it there is between the soul and God a union akin to marriage. “I will espouse you in faith” [Hosea 2:20].
2) The second effect of faith is that eternal life is already begun in us; for eternal life is nothing else than knowing God. This the Lord announced when He said: “This is eternal life, that they may know you, the only true God, and Jesus Christ whom you sent” [Jn 17:3].
3) The third good that comes from faith is that right direction which it gives to our present life. “The just man lives by faith” [Hab 2:4].
4) The fourth effect of faith is that by it we overcome temptations: “The holy ones by faith conquered kingdoms” [Heb 11:33].
* Quotations taken from Expositio in Symbolum Apostolorum, THE APOSTLES' CREED by Thomas Aquinas, translated by Joseph B. Collins, New York, 1939.