2. Jesus had already asked the group of the 12 Apostles to profess their faith in his person. At Caesarea Philippi, after questioning his disciples about the people's opinion of his identity, he asks: "But who do you say that I am?" (Mt 16:15). The reply comes from Simon Peter: "You are the Christ, the Son of the living God" (16:16).
Jesus immediately confirms the value of this profession of faith, stressing that it stems not only from human thought idea but from heavenly inspiration: "Blessed are you, Simon Bar-Jona! For flesh and blood has not revealed this to you, but my Father who is in heaven" (Mt 16:17). These statements, in strongly Semitic tones, indicate the total, absolute and supreme revelation: the one that concerns the person of Christ, Son of God.
Peter's profession of faith will remain the definitive expression of Christ's identity. Mark uses this same expression to begin his Gospel (cf. Mk 1:1) and John refers to it at the end of his, saying that he has written his Gospel so that you may believe "that Jesus is the Christ, the Son of God", and that in believing you may have life in his name (cf. Jn 20:31).
3. In what does faith consist? The Constitution Dei Verbum explains that by faith, "man freely commits his entire self to God, making 'the full submission of his intellect and will to God who reveals'" (n. 5). Thus faith is not only the intellect's adherence to the truth revealed, but also a submission of the will and a gift of self to God revealing himself. It is a stance that involves one's entire existence.
The Council also recalls that this faith requires "the grace of God to move [man] and assist him; he must have the interior helps of the Holy Spirit, who moves the heart and converts it to God, who opens the eyes of the mind and 'makes it easy for all to accept and believe the truth'" (ibid.). In this way we can see how, on the one hand, faith enables us to welcome the truth contained in Revelation and proposed by the Magisterium of those who, as Pastors of God's People, have received a "sure charism of truth" (Dei Verbum, n. 8). On the other hand, faith also spurs us to true and deep consistency, which must be expressed in all aspects of a life modeled on that of Christ.
[Pope John Paul II, General Audience 18 March 1998]