When you hear the word "church," what comes to mind? A building? A religious institition? A priest or a saint?
The Church is, among other things, people. God's people. The people he gathers in the whole world. The Church is lived in local communities and is seen and becomes real when her members pray together, especially at Mass. The Church is a family of believers. And this family is marked by certain characteristics (CCC 782):
The oldest declaration of the Christian faith, the Nicene Creed, was adopted in 325 AD, even before the canon of the Bible was difinitively closed. The leaders of the Catholic faith needed a method of proclaiming salvation that was shareable and memorable and retained the core truth of the Gospel and the teachings of the apostles. In 381, the Nicene Creed was expanded with additional points of doctrine. Catholics around the world continue to profess this form of the creed every Sunday at Mass.
Catholics believe that God is the creator and sustainer of all things. God loves us and created us to be in relationship with Him in perfect harmony. We sinned and broke our relationship with God. We separated ourselves from Him and His plan for our lives. God created us for life and happiness, and sin always leads to death and suffering.
God the Father does not want us to suffer and die, so He sent His beloved Son, Jesus, to become man to redeem us from our sins. Jesus, who is God incarnate and not created, is both fully God and fully man. He is the Word through whom the entire universe was created. He came to us to heal our relationship with God through His life, death, and resurrection and to establish the Church.
The Holy Spirit is also God, the third person of the Trinity. The Holy Spirit is our advocate, helper, and provider. Jesus not only offered us the free gift of eternal salvation but also promised to send us a helper in choosing grace and living the Christian life. That helper is the Holy Spirit, who first came to the apostles on Pentecost and who comes to us through our baptism and confirmation. The Holy Spirit helps us to live according to God's plan for our lives.
God also gives us the Church to be His sacramental presence on earth. That Church is:
"All are welcome in the Church, but not on their terms - on Christ's terms."
- Bishop Robert Barron