Sometimes people make it sound like the Catholic understanding of how to get to heaven is really complex.
Its not.
While you can go into any of Christs teachings in a lot of very rich detail, he made sure that this one can be understood even by a child.
I can summarize it in two sentences.
The two sentences are these: To come to God and be saved, you need to repent, have faith, and be baptized. If you commit mortal sin, you need to repent, have faith, and go to confession.
Thats it. Thats all there is to it. And we can show each of these things from the Bible.
The need to repent is shown by the fact that, right at the beginning of his ministry, Jesus began preaching the gospel, saying repent and believe in the gospel (Mark 1:14-15).
The need for faith is shown when the author of the letter to the Hebrews writes that Without faith it is impossible to please him. For whoever would draw near to God must believe that he exists and that he rewards those who seek him (Heb. 11:6).
And the need for baptism is shown when St. Peter flatly tells us: Baptism now saves you (1 Peter 3:21).
So thats what you need to do if you want to come to God and be saved: Repent, have faith, and be baptized.
If you do these things, youll be in a state of grace, and as long as you remain in a state of grace, youll go to heaven.
But we still have free will, and we can still turn our backs on God and fall from grace, to use St. Pauls phrase (Galatians 5:4).
St. Paul is very clear about the possibility of us committing mortal sin. He tells us: Do not be deceived; neither the immoral, nor idolaters, nor adulterers, nor homosexuals, nor thieves, nor the greedy, nor drunkards, nor revilers, nor robbers will inherit the kingdom of God (1 Corinthians 6:9-10).
To turn away from God and commit mortal sin is the opposite of repenting. So when we fall into mortal sin, we need to turn back to Godto repent again.
We also need to have faith.
And then we need to go to confession. This is something Jesus indicated just after he rose from the dead. He came to his disciples, breathed on them, and said, Receive the Holy Spirit. If you forgive the sins of any, they are forgiven; if you retain the sins of any, they are retained (John 20:22-23)
So Jesus empowered his ministers to forgive or retain sins. In order for a priest to know whether he is to forgive or retain a sin, he needs to know about the sin and whether we have repented of it. That means we need to go and tell him these things, and so we have the sacrament of confession.
So thats what you need to do. To come to God and be saved, you need to repent, have faith, and be baptized. If you commit mortal sin, you need to repent, have faith, and go to confession.
Its all thoroughly biblical.