Prayer
O my God, I firmly believe that Thou art one God in three Divine Person, Father, Son, and Holy Spirit; I believe that Thy Divine Son became man, and died for our sins, and that He will come to judge the living and the dead. I believe these and all the truths which the Holy Catholic Church teaches, because Thou hast revealed them, who canst neither deceive nor be deceived. Amen.
Acts of Faith are common in morning prayers, and they should be said at any time in which we feel our faith is being tested or we are enduring temptation.
By the time children are preparing for Catholic Confirmation, it is definitely good to know Acts of Faith, Hope, and Charity. They ask for the main graces necessary to keep the Faith and die well.
The Act of Faith sums up the Apostles' Creed. It also gives the reason Catholics believe in the Blessed Trinity: God Himself revealed it. Whether or not we can understand a revelation, we believe it because He Who is Omniscient, All-Knowing, revealed it!
In morning prayers, an Act of Faith is traditionally followed by an Act of Hope and an Act of Charity.