|Father William Most|
The fundamental truth about Catholicism centers around the reality of Jesus as both man and God, as well as his creation of the Catholic Church through which he is "with us always." In his book, Free From All Error, Fr. William Most establishes six historical facts about Jesus and what he did while he was on the Earth that allow us to move forward with a reasoned faith. Let's look at these facts, which we've adjusted slightly and condensed down to five, on which we can base our trust in Catholicism:
- "There was a man called Jesus."
- Jesus's historicity is beyond doubt.
- Claims to be a messenger: "For God so loved the world that he gave his only Son, that whoever believes in him should not perish but have eternal life. For God sent the Son into the world, not to condemn the world, but that the world might be saved through him" (John 3:16-17).
- Claims to be God: "Jesus said to them, 'truly, truly I say to you, before Abraham was, I am.'" (John 8:58)
- Jesus says of himself "I am" referring to God's name given to Moses in Exodus 3:14. Every Jew knew exactly what he was saying, this is why, in the very next line, "they took up stones to throw at him."
- "Jesus often appealed to his miracles as proof of his mission and teaching:"
- "Now when John heard in prison about the deeds of the Christ, he sent word by his disciples and said to him, 'are you he who is to come, or shall we look for another?' And Jesus answered them, "Go and tell John what you hear and see: the blind receive their sight and the lame walk, lepers are cleansed and the deaf hear, and the dead are raised up, and the poor have good news preached to them." (Matthew 11:2-5)
- William Most notes that "God is the ultimate source of the miraculous power...and He cannot provide such power as proof of a falsehood." In other words, if God is the source and ultimate author of all that is miraculous, He would not allow someone to cause miracles in his own name if he were not God. All other miracles performed by humans are done in God's name. Jesus, however, always performs them in his own name, because he claims to be God.
- Jesus proved that he was God by the success of his miracles and in the Resurrection.
- Father Robert Barron summarizes N.T. Wright's explanation of the Resurrection's credibility: "There would be no clearer indication for a first century Jew that somebody was not the Messiah than his death at the hands of Israel's enemies...The anointed one of Israel was meant to deal with the enemies of Israel...and to reign as the Lord of the nations. Therefore the clearest sign possible that somebody was not the Messiah was that he was put to death by the Romans. And of course you can hear that even in the Gospels can't you? The disciples run away when this happens. The disciples on the road to Emmaus say, ironically to Jesus himself, 'we thought he was the Messiah,' the implication being that clearly he's not. One thing you know for sure is that he's not the Messiah because the Romans killed him! Therefore, N.T. Wright says this: what's really weird from an historical standpoint...is how Christianity emerged as a Messianic movement. Because that's the claim of Paul and the others," that Jesus is in fact the Messiah. "The only way, N.T. Wright says, to make sense of this from an historical standpoint, is that Jesus rose from the dead."  None of the modern theories that attack Jesus's divinity would have carried any weight at all in the conversion of the first century Jews. Why would the first Christians continue on in their faith if Jesus had not risen from the dead? To be martyred? They continued on in their faith because it was true.
- "And he went up on the mountain, and called to him those whom he desired; and they came to him. And he appointed twelve, to be with him, and to be sent out to preach and have authority to cast out demons. (Mark 3:13)
- "And Jesus came and said to them (the twelve minus Judas), 'All authority in Heaven and on Earth has been given to me. 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, teaching them to observe all that I have commanded you.'" (Matthew 28:18-20)
- "Jesus says to them, 'but whom do you say that I am?' Simon Peter answered and said: 'You are Christ, the Son of the living God.' And Jesus answering said to him, 'blessed are you Simon Bar-Jona: because flesh and blood has not revealed it to you, but my Father who is in heaven. And I say to you that you are Peter; and upon this rock I will build my Church, and the gates of Hell shall not prevail against it. And I will give you the keys to the Kingdom of Heaven. And whatsoever you shall bind upon Earth, it shall be bound also in Heaven: and whatsoever you shall loose on Earth, it shall be loosed also in Heaven.'" (Matthew 16:15-19)
- "These things I have spoken to you while I am still with you, but the Counselor, the Holy Spirit, whom the Father will send in my name, he will teach you all things, and bring to your remembrance all that I have said to you." (John 14:25-26)
- "He who hears you hears me; he who rejects you rejects me, and he who rejects me rejects him who sent me" (Luke 10:16).
- "'I say to you that you are Peter; and upon this rock I will build my Church, and the gates of Hell shall not prevail against it. And I will give you the keys to the Kingdom of Heaven. And whatsoever you shall bind upon Earth, it shall be bound also in Heaven: and whatsoever you shall loose on Earth, it shall be loosed also in Heaven.'" (Matthew 16:15-19 again)
- "These things I have spoken to you while I am still with you, but the Counselor, the Holy Spirit, whom the Father will send in my name, he will teach you all things, and bring to your remembrance all that I have said to you." (John 14:25-26 again)
- Jesus promises here that the Holy Spirit will be given to the Apostles so that their teaching will always be from God.
- '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, teaching them to observe all that I have commanded you. And behold, I am with you all days, even to the consummation of the world. (Matthew 28:18-21; bold is DR Version)
- "Again the Kingdom of Heaven (membership in the Church which is Christ's body) is like a net cast into the sea, and gathering together all kinds of fishes. Which, when it was filled, they drew out, and sitting by the shore, they chose out the good into vessels, but the bad they cast forth. So it shall be at the end of the world. The angels shall go out, and shall separate the wicked from among the just."
- The Church will be gathering together all kinds of people until the end of the world.
*Note: Some people would object and say that Jesus is not doing anything special with the Apostles; they would say his message is actually intended for everyone. This is true to some degree, but we cannot deny the particular mission of the Apostles as the teaching mouth of Christ. As George Joyce notes, Jesus is "distinguishing in an unmistakable manner, between the private individual who undertakes the work of fraternal correction and the ecclesiastical authority empowered to pronounce a judicial sentence:" "But if your brother shall offend against you, go, and rebuke him between you and him alone. If he shall hear you, you shall gain your brother. And if he will not hear you, take with you one or two more: that in the mouth of two or three witnesses every word may stand. If he will not hear them: tell the Church. And if he will not hear the Church, let him be to you as the heathen and publican." (Matthew 18:15-17) 
Conclusion: Based on the clear and undeniable truth of these five facts, we are rooted in the truth of Christ's Catholic Church. We can see clearly that Jesus, after an entire night in prayer (Luke 6:12), called the apostles together (12 specifically to signify the typological fulfillment of Israel's twelve tribes; the Old Covenant "church" becomes the New Covenant, Catholic Church), gave them a commission to carry on his teaching, and promised their protection from error.
 Father William Most; Free From All Error
 Father Robert Barron; Is Our Faith in the Resurrection Credible?
 George Joyce; Catholic Encyclopedia Article The Church