The Catechism of the Catholic Church tells us that the Apostles’ Creed is “a faithful summary of the apostles’ faith.” And St. Ambrose comments: “This Creed is the spiritual seal, our heart’s meditation, and an ever-present guardian; it is, unquestionably, the treasure of our soul.”
Praying the Apostles’ Creed is an act of faith. St. Thomas Aquinas tells us, “The first thing that is necessary for every Christian is faith, without which no one is truly called a faithful Christian.” He notes four effects of faith in our lives:
“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].
“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’ [John 17:3].
“The third good that comes from faith is that right direction which it gives to our present life. ‘The just man lives by faith’ [Habakkuk 2:4].
“The fourth effect of faith is that by it we overcome temptations: ‘The holy ones by faith conquered kingdoms’ [Hebrews 11:33].