The core beliefs of Christianity center on who God is and what he has done to save us. Three doctrines sit at the foundation. First, the Bible is God’s inspired Word and always tells the truth. Second, God is one being who exists eternally as three persons: Father, Son, and Holy Spirit. Third, Jesus accomplished the atonement, living a perfect life and dying in our place to pay for our sins once for all.
The Bible Is God’s Word
Every belief system needs a final authority. For some people it’s personal feelings, for others it’s culture or tradition. Christians believe the final authority is the Bible. That’s because the Bible isn’t just a collection of human opinions about God. It’s God’s own message to us, written through human authors.
2 Peter 1:20-21 Above all, you must understand that no prophecy of Scripture came about by the prophet’s own interpretation of things. For prophecy never had its origin in the human will, but prophets, though human, spoke from God as they were carried along by the Holy Spirit.
Peter explains that Scripture didn’t originate in human imagination. The Holy Spirit carried the writers along so that what they wrote was exactly what God intended. That’s what Christians mean when we say the Bible is inspired. And because God doesn’t lie, his Word is trustworthy.
This has practical consequences. When the Bible says something we don’t like or don’t understand, we submit to it rather than editing it to fit our preferences. That doesn’t mean we stop asking questions. It means we come to Scripture humbly, trusting that God sees more clearly than we do.
God Is One God in Three Persons
The Bible is clear that there is only one God. It’s just as clear that the Father is God, the Son is God, and the Holy Spirit is God. Christians call this the Trinity. Paul affirms both the oneness of God and the full deity of Jesus in the same breath.
1 Corinthians 8:6 …yet for us there is but one God, the Father, from whom all things came and for whom we live; and there is but one Lord, Jesus Christ, through whom all things came and through whom we live.
John’s Gospel opens by describing Jesus as the Word who was with God in the beginning and who was God.
John 1:1-4 In the beginning was the Word, and the Word was with God, and the Word was God. He was with God in the beginning. Through him all things were made; without him nothing was made that has been made. In him was life, and that life was the light of all mankind.
The Trinity isn’t three gods, and it isn’t one God wearing three different masks. It’s one God who exists eternally in three distinct persons who love and relate to each other. That’s hard for our minds to grasp, and that’s okay. A God we could fully figure out wouldn’t be much of a God. The early church summarized this teaching carefully, and you can learn more in What Is the Athanasian Creed?
Jesus Paid for Our Sins
The word atonement describes how sinful people are made “at one” with a holy God. Our sin created a gap we couldn’t close on our own. Jesus closed it. Hundreds of years before he was born, Isaiah described what the Messiah would do.
Isaiah 53:4-6 Surely he took up our pain and bore our suffering, yet we considered him punished by God, stricken by him, and afflicted. But he was pierced for our transgressions, he was crushed for our iniquities; the punishment that brought us peace was on him, and by his wounds we are healed. We all, like sheep, have gone astray, each of us has turned to our own way; and the Lord has laid on him the iniquity of us all.
Jesus took the punishment we deserved. He absorbed God’s righteous wrath against sin so that we could be forgiven. Paul puts it this way: God made him who had no sin to be sin for us, so that in him we might become the righteousness of God (2 Corinthians 5:21). Peter adds that Jesus bore our sins in his body on the cross so that we might die to sin and live for righteousness (1 Peter 2:24). And this sacrifice was once for all. Nothing needs to be added to it.
The atonement is the heart of the gospel. It’s why Christians call the news about Jesus good news. If you’d like to learn more about putting your faith in Jesus, check out How can I become a Christian?
The Takeaway
What are the core beliefs of Christianity? The Bible is God’s inspired, trustworthy Word. God is one being in three persons: Father, Son, and Spirit. And Jesus made atonement for our sins through his life and death. These truths are the foundation every follower of Jesus can build on.
