When the Apostles went forth into the world after the Resurrection and Ascension of Christ, they did not preach a vague spirituality or a mere moral philosophy. They proclaimed a Person — Jesus Christ crucified and risen — and they proclaimed Him with conviction because they themselves had come to know Him as the fulfillment of everything God had promised. In the Acts of the Apostles, we hear of Apollos and of Saint Paul “vigorously” proclaiming and defending the truth that Jesus is the Christ. Their preaching was not rooted in emotion alone, nor in blind zeal, but in a deep knowledge of the Scriptures, the promises of God, and the saving work of Christ. They understood not only that they believed, but why they believed.
This is essential for every Christian disciple. Faith is not meant to remain private, fragile, or unexamined. The believer is called to love God not only with the heart, but also with the mind. To know the faith deeply is to be able to recognize the hand of God throughout salvation history — from the covenant with Abraham, to the Law given through Moses, to the prophets who foretold the Messiah, and finally to Christ Himself, who fulfills all things. Saint Paul could stand before Jews, Greeks, philosophers, governors, and persecutors because he knew the Scriptures and could demonstrate how every promise converged upon Jesus. His confidence came not from pride in his own intellect, but from certainty in the truth.
There is also a profound pastoral importance in knowing the faith. The world continually asks questions: Why believe in God? Why trust the Church? Why does suffering exist? Why did Christ have to die? Why does the Eucharist matter? Why should one follow Christ rather than merely live according to personal desire? If Christians cannot answer these questions — even imperfectly — the faith risks appearing to others as inherited custom rather than living truth. But when a believer can speak thoughtfully and faithfully about Christ, the Gospel becomes credible and compelling. Knowledge gives clarity to witness.
Knowing the faith also strengthens perseverance. A believer who understands the foundations of Christianity is less easily shaken by suffering, doubt, cultural opposition, or false teaching. The storms of life inevitably come, and emotional fervor alone can fade under hardship. But a faith rooted in understanding becomes enduring. One who knows why Christ is trustworthy can remain faithful even in seasons when feelings are absent. Knowledge deepens conviction, and conviction strengthens endurance.
The early Christians changed the world because they were convinced that Jesus truly was the promised Messiah, the Son of God, and Savior of the world. Their witness was courageous because it was grounded in the truth they had come to know deeply. The same calling remains for Christians today. The disciple of Christ is not merely called to believe silently, but to be ready, as Saint Peter writes, to “give an explanation to anyone who asks you for a reason for your hope”. To know the faith, then, is not optional for the Christian life; it is part of loving God fully and participating in the mission Christ entrusted to His Church — to proclaim the Gospel to all nations.