Christ commanded his disciples in Matt 28:19-20 to teach all he had given them:
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19”Go therefore and make disciples of all nations, baptizing them in the name of the Father and of the Son and of the Holy Spirit, 20 and teaching them to obey everything I have commanded you. And remember, I am with you always, to the end of the age."*
This is Jesus’ promise which he will keep always.
Jesus empowered the Apostles and gave them authority in Lk 10:16 Jesus when he said
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“Whoever listens to you, listens to me, and whoever rejects you rejects me.” *
Here we were told that those listening to the authority of the Church are listening to Christ himself. As the Word spread throughout the world there was a need for a central authority. Remember that the heretics were there from the beginning – the Church had to fight them from the very beginning.
At the last Supper Jesus prayed that his disciples would remain united as he and the Father are (John 17:11)
“And now I am no longer in the world, but they are in the world, and I am coming to you. Holy Father, protect them in your name that you have given me, so that they may be one, as we are one.”
It is essential that we be united in Faith. We are to be One, Holy, Catholic and Apostolic. That is why Jesus said those words that we are to be one.
Today everywhere we have the evidence of a divided Christianity. This is because people have been dissatisfied with what the original Church taught and have started breakaway movements. Yet Jesus promised that the Holy Spirit would be with the Church, guiding into all truth (John 16:13)
“When the Spirit of Truth comes he will guide you into all the truth; for he will not speak on his own, but will speak whatever he hears and he will declare to you the things that are to come.”
Despite heresies, bad popes, bad clergy, the Holy Spirit has guided the Church and steered us on the right path and away from error.
Those who left and started their own churches and denominations have separated themselves from the Church and its authority
Jesus gave Peter “the keys of the kingdom of heaven (Matt:16-18-19)
- “And I tell you, you are Peter, and on this rock I will build my Church and the gates of Hades will not prevail against it. 19 I will give you the keys of the Kingdom of Heaven and whatever you bind on earth will be bound in Heaven and whatever you loose on earth will be loosed in Heaven.”*
Jesus recognized the need for authority and that is why he gave the keys to Peter.
It is clear as crystal that the Church is to be One under Peter and the Apostles and those who isolate themselves are suspect. (2 Peter 2:1) warns of false teachers spreading bad doctrine. Christ himself warns about false prophets leading people astray even while performing miracles
“But false prophets also arose among the people, just as there will be false teachers among you, who will secretly bring in destructive opinions, they will even deny the Master who bought them – bringing swift destruction on themselves."
We in the Catholic Church believe that all Christians are part of the Body of Christ (His Church) but they are separated brethren because they rejected some of the teachings of the Church. This does not mean that they will not be saved. They inherited the separated church which began with Luther and his ilk. God is merciful and will never reject them.
Despite recognizing all Christians as being part of the Body of Christ, and therefore have a claim to salvation, we cannot say that they are in fully communion with the Body of Christ because they have separated themselves from “FULL COMMUNION”.
I am sure that those more knowledgeable than myself will add to my post and correct me if I am wrong.
Peace
Cinette