The Church: Why Did Jesus Found One?
Jesus founded one Church on the apostles, with Peter as its rock, to carry His life and teaching to the whole world. It is holy because of Christ, even though its members are sinners.

Jesus could have left behind a book or a set of ideas. Instead He gathered people. He called twelve apostles, lived with them for years, gave them authority to teach, forgive and celebrate the Eucharist, and promised to stay with them always (CCC 765). He prayed that all His followers would be one, so that the world would believe.
At the head of the Twelve He placed Simon, giving him a new name: Peter, which means rock. Upon this rock I will build my church, He said, and He gave Peter the keys of the kingdom (CCC 881). The Pope, as Bishop of Rome, is Peter's successor, and the bishops are the successors of the apostles (CCC 862, 882).
The Church was born from Christ's total gift of Himself on the cross and was revealed to the world at Pentecost (CCC 766-767). St Paul calls it the Body of Christ: Christ is the head, and we are the members. The Church is both visible, with real leaders, buildings and sacraments, and spiritual, united by grace (CCC 779, 789).
In the Creed we profess four marks of the Church: one, holy, catholic and apostolic (CCC 811). The Church teaches that the one Church of Christ subsists in the Catholic Church, governed by Peter's successor and the bishops in communion with him (CCC 816).
The obvious objection: the Church is full of sinners, and some have done terrible harm. That is true, and the Church does not hide it. She is holy because Christ makes her holy, not because her members always are. She holds sinners to her heart and is always in need of purification (CCC 823, 827). A hospital is not discredited because it is full of sick people.
What about other Christians and other religions? The Church recognizes that baptized Christians outside her visible bounds are joined to her in real ways, and that many elements of truth and holiness are found there (CCC 819, 838). The old saying, outside the Church there is no salvation, means that all salvation comes from Christ through His Body. Those who, through no fault of their own, do not know Christ or His Church, yet seek God sincerely and try to do His will, can be saved (CCC 846-848).
Key points
- Jesus founded a visible community, the Church, built on the apostles with Peter as the rock.
- The Pope is Peter's successor and the bishops are successors of the apostles.
- The Church is one, holy, catholic and apostolic, though her members are sinners.
- All salvation comes from Christ through His Church, and God can reach those who never knew it through no fault of their own.
The Word of God
And I say to thee: That thou art Peter; and upon this rock I will build my church, and the gates of hell shall not prevail against it.
That they all may be one, as thou, Father, in me, and I in thee; that they also may be one in us; that the world may believe that thou hast sent me.
But if I tarry long, that thou mayest know how thou oughtest to behave thyself in the house of God, which is the church of the living God, the pillar and ground of the truth.
Catechism paragraphs for this lesson
- CCC 763-766
- CCC 811-816
- CCC 823-827
- CCC 881-882
- CCC 846-848
CCC means the Catechism of the Catholic Church. Saints Light teaches it in its own words and never quotes it. Look up any paragraph in a printed copy or at vatican.va. See every lesson by paragraph in the Catechism index.
From the tradition
Q. Who is the invisible Head of the Church? A. Jesus Christ is the invisible Head of the Church. Q. Who is the visible Head of the Church? A. Our Holy Father the Pope, the Bishop of Rome, is the Vicar of Christ on earth, and the visible Head of the Church.
Live it this week
Look up your local Catholic parish online this week and find two things: the Sunday Mass times and the name of the pastor. If you can, go to one Mass and simply watch and listen.
Check yourself: three questions
1. Why did Jesus give Simon the name Peter?
- Because Simon was the oldest apostle
- Because it was a common family name
- Because Simon would write most of the New Testament
- Because Peter means rock, and Christ would build His Church on him
Show the answer
Because Peter means rock, and Christ would build His Church on him. Peter means rock; Jesus said He would build His Church on this rock and gave him the keys (Matthew 16:18; CCC 881).
2. How can the Church be holy when her members sin?
- Christ makes her holy, while she always needs purification
- Her members never commit serious sins
- Holiness only describes the clergy, not the laity
- The Church is not actually called holy
Show the answer
Christ makes her holy, while she always needs purification. The Church is holy through Christ yet embraces sinners and is always in need of purification (CCC 823, 827).
3. What does outside the Church there is no salvation mean, read positively?
- Only those who attend Mass every week can be saved
- Every non-Catholic is certainly lost
- All salvation comes from Christ through His Body, the Church
- Salvation depends on where you were born
Show the answer
All salvation comes from Christ through His Body, the Church. Reformulated positively, it means all salvation comes from Christ the Head through the Church, His Body (CCC 846-848).
Words to know
- Apostolic succession
- The unbroken handing on of the apostles' authority to the bishops through ordination.
- Body of Christ
- St Paul's name for the Church: Christ is the head, and the faithful are His members.
More terms in the Catholic glossary. More passages in the Scripture index.
For catechists: a one hour class plan
Goal. The group should understand that Jesus founded one visible Church on the apostles, with Peter as the rock, and that the Church is holy because of Christ even though her members are sinners.
Opener. Ask: "Think of a community that shaped you: a family, team, school or parish. What made it more than a group of individuals?" Let a few people share, then note that Jesus chose to gather a people, not to write a book.
Discussion questions
- Why do you think Jesus founded a visible community instead of leaving only teachings? [We are social; He wanted His life carried in a people with real authority (Matthew 16:18). Avoid dismissing other Christians.]
- How can the Church be holy when its members, including clergy, have sinned badly? [Holiness comes from Christ, not from us. Be honest about scandals; do not minimize hurt. If someone is carrying a wound from the Church, listen and offer a conversation with the priest.]
- What do the four marks, one, holy, catholic and apostolic, tell you about the Church? [Each points to Christ's gifts. Keep it simple: united, made holy by Christ, for everyone, and handed down from the apostles.]
- What does the Church teach about people who never knew the Church through no fault of their own? [All salvation comes from Christ through His Church, and God can reach them in ways He knows. This matters for members with family of other faiths; speak with charity.]
Activity. Church walk: if you meet in the parish, walk together into the church for 12 minutes. Stop at the font, the altar, the ambo and the chair, and ask: "What does this tell us about how Jesus stays with His Church?" If you cannot go in, look up the parish website together and find the Mass times, the pastor's name and the patron saint.
Closing prayer. Lord Jesus, You gathered Your apostles and promised to stay with Your Church always. Thank You for this parish and for everyone who brought the faith to us. Forgive the sins of Your people, heal those who have been hurt, and make us one, so the world may believe. Amen.
Timing. Opening prayer 5 min, opener 5 min, read the lesson together 15 min, discussion 20 min, activity (church walk) 12 min, closing 3 min.
Related lessons
- the holy catholic Church, the communion of saints (The Creed, free)
- What About the Scandals? (Hard Questions)
- Are Non-Catholics Saved? (Hard Questions)
- Where Is the Pope in the Bible? (Hard Questions)
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