There are certain aspects of the Christian worldview that many people find objectionable. The man with the unregenerate heart will not enjoy hearing that Jesus Christ is the only way to salvation. The individual who aspires for moral autonomy will posit a form of relativism, suggesting that you cannot impose your morals upon them. The doctrine of Hell, the depravity of man and the need for forgiveness repel us. This has led the people of this generation to challenge the foundation for all of it. If you can compromise the inerrancy of the Bible, then one can justify their preferred lifestyle. They do not have to be concerned about marriage or abortion, and can breathe the air free from the sovereignty of God. As man flees the sovereignty of God, he will pose the question, “How do you know that the Bible is God’s word?”
Criticisms of the biblical data have come in several different forms. Scholars like Dr. Bart Ehrman will make their career and their living arguing that we cannot trust the Scripture, that we cannot know what the authors of the New Testament originally wrote in the absence of some sort of controlled and monitored transmission of the text of Scripture. Others will suggest that the text is plagued with historical errors and contradictions, compromising the reliability of the text. Still some will posit that the Bible portrays an unscientific view of the world. If you are interested in my response to the negative case against the Bible, feel free to review some of the linked articles or just use the search function. Instead, as I answer the question, “How do you know that the Bible is God’s word?” I will present a positive case regarding why I choose to believe in the Bible.
The Historicity of The New Testament
While most people know the New Testament as the holy text of the Christian religion, it functions as more than that in the academic world. If a historian wants to learn about Jesus and the apostles, he needs historical data. The New Testament is a collection of the the primary sources that he or she will need to use. This means that one can use the New Testament to probabilistically conclude that certain events are historical or not historical. Now, I know that many people will take a surface glance at this answer to the question, “How do you know that the Bible is God’s word?” and feel tempted to blurt out, “You’re reasoning in a circle!” I urge you to resist that temptation. This is not circular reasoning. It would only be circular if I were assuming that the Bible were God’s word and is therefore inerrant. Rather, the task of the historian is to apply the same principles of historical investigation to the New Testament that they would apply to any ancient document. (By the way, if you are a presuppositionalist and preparing to accuse me of impiety, please read my article Is The Minimal Facts Argument Impious?)
So, with that in mind, when one applies the principles of historical investigation to the New Testament, the historian establishes a few facts surrounding the death of Jesus. As I argued in my article Did Jesus Rise From The Dead? a few of these facts include  the burial of Jesus,  the empty tomb,  the post-mortem appearances and  the perseverance of the disciples’ belief in the resurrection. The most probable explanation of these facts that far outstrips any naturalistic hypothesis is that God raised Jesus from the dead.
Okay, you are likely wondering how I connect that with the New Testament. After all, as I pointed out, this argument does not require an inerrant or even inspired Bible. So, you may reassert the question, how do you know that the Bible is God’s word? Well, I suggest that it is more probable that after Jesus rose from the dead, the religion that was preached by his disciples is true. If God raised Jesus from the dead, then he obviously wanted the world to hear his message. This message is contained in the writings of the disciples and the Christian religion. Therefore, we know that the Bible is God’s word because Jesus rose from the dead and commissioned his disciples to preach his message.
How Jesus Viewed The Scripture
The premise that God raised Jesus from the dead has several implications. If Jesus had remained dead, he would have been proven to be a blasphemer. Deuteronomy 21:23 tells us, “Cursed is everyone who hangs on a tree.” The Jewish Sanhedrin who prosecuted Jesus would have been vindicated and their counter-arguments about Jesus would have been justified. As Paul writes in 1 Corinthians 15:17, “If Christ is not risen, we are most of all to be pitied.” However, if God raised Jesus from the dead, vindicating his claims, then as Paul said in Galatians 3:13, Christ was under the curse of God on our behalf. He died the death that we deserve, absorbing our sins and then he rose from the dead. But if this man rose from the dead, we would be confronted with several other questions as well. We would have to ask why God raised him from the dead, who he was, what he said about himself and what he said about the Scripture.
The principles of historical investigation yield several startling facts about how Jesus viewed himself. First, the parable of the wicked tenants in the gospel of Mark meets the criteria of multiple attestation and is usually ascribed to the portrait of the historical Jesus. In this parable, he describes himself as God’s own Son and heir to his kingdom. Second, Jesus referred to himself on several occasions as the Son of Man, hailing from Daniel’s eschatological vision in the seventh chapter of the book named after him. The Son of Man was one who all of the people of the nations would worship. But it is startling that the Christians of the first century did not use that title. While it was Jesus’s favorite self-designation, it is scarce in the pages of the New Testament. This means that it meets the criteria of dissimilarity and is properly ascribed to the historical Jesus.
While this does not exhaust the historically verifiable claims that Jesus made of himself, they are potent enough that we can proceed. Jesus claimed to be both the Son of God and the Son of Man. He claimed to be the Messiah. Then he died and rose from the dead. His view of Scripture should be quite significant for us as we establish a proper view of the Bible. Jesus made claims such as “The Scripture cannot be broken” (John 10:35). He said “For truly I say to you, until heaven and earth pass away, not the smallest letter or stroke shall pass from the Law until all is accomplished.” (Matthew 5:18). How do we know that the Bible is God’s word? Well, Jesus believed that the Scripture was without error and was God-breathed. As the one who claimed to be the Son of God, Son of Man, died and rose from the dead, he is a worthy authority.
An obvious objection to this argument arises. One may point out that Jesus believed in what we call the Old Testament. What about the New Testament? Well, Jesus’s statements were related to the nature of Scripture, not the scope of Scripture. But, then one may ask how it is that we distinguish between the Roman Catholic Bible (containing the apocrypha) and the 66 books of the Bible used in Protestantism. That is certainly a valuable question. But the point that I am making is that on the authority of the one who rose from the dead, we should believe the religion that he left behind. Those who are striving to believe in that religion may debate amongst themselves about what the true faith is. I am personally a Protestant (more specifically, a Calvinist).
I am hesitant to include this line of argumentation because it is precisely what one would expect when talking to a person of any religious background. People believe in their faith because there was some fulfilled prophecy. God relayed some knowledge that could not otherwise be known. This is the same sort of argument that people will use when they go to a psychic. They will tell us, “They knew things about me that they could not have possibly known!” Muslims and Hindus will likewise tell us that they know their faith claims to be true because some prophecy has been fulfilled. I understand that this might strike you as a familiar and restated argument. I also believe that if you closely scrutinized most prophetic claims, they would either  quickly unravel or  they would be unfalsifiable. I believe that when one takes a close look at the prophecies throughout the Bible, they become firmer and better attested.
The prophecy to which I would like to draw your attention is the destruction of Jerusalem in AD 70. Jesus said in Mark 13:2, “Do you see these great buildings? Not one stone will be left upon another which will not be torn down.” The Temple was the center of the Jew’s religious life. It was everything to them. They believed that God himself resided in the Temple. They could not fulfill their obligations to their faith if they were not in Jerusalem with an active Temple. So when Jesus said that the Temple would be destroyed, that must have been a startling claim. It is something like if he suggested that the Twin Towers were going to fall. So, the gospels record him as saying this, and yet no one records that Jerusalem had actually been destroyed. As far as we can tell, in all of the gospels and all of the epistles, the Temple is still standing and Jerusalem has not been overrun. If it had been written after AD 70, it would be unthinkable that the disciples would not have mentioned “Oh, by the way, this was a fulfilled prophecy. Jesus predicted that it would happen, and it did.” That would have been a powerful argument that he was the Messiah. Yet we do not see it anywhere throughout the New Testament.
The probabilistic conclusion that I draw from this is that the synoptic gospels were written prior to AD 70. They record Jesus making this fantastic prediction before it was actually fulfilled. How do you know that the Bible is God’s word? We know that it is God’s word because the criteria of historical investigation unveils legitimate fulfilled prophecy.
The Christian Worldview Makes Sense of Reality
Everybody makes assumptions and everybody has a worldview. You might not think that you do, but it is unavoidable. You will interpret reality through the lens of your worldview. It is something like navigating through the world with a map. If you have an inaccurate map, you will struggle to get through the terrain. Similarly, if you have an inaccurate worldview, you will struggle to make any sense of reality. The Christian worldview makes more sense of reality than any other competing worldview. Indeed, unless you assume the Christian worldview, you will not be able to make any sense of the world in which you inhabit. This worldview is informed and defined by Scripture.
First, the Christian worldview informs us that God exists. As I argued in my article What Would A Universe Without God Look Like? a universe without God would look radically different from a universe in which God exists.  There would not be any intelligent lifeforms (such as human beings).  The evolution of biological organisms would be impossible.  Our cognitive faculties would not be functional.  Most importantly, if God did not exist, the universe would not exist. Since the universe is not necessary in its’ existence (we know that because it has not always existed), it must have an explanation beyond itself. Since the cause must transcend its’ effect, the explanation of the universe must be timeless, spaceless, eternal, uncaused, and supernatural. Since the Christian worldview contains the assumption that God exists, it makes sense of this reality, while a secular or naturalistic worldview would not. The secular presuppositions do not even permit them to have a universe, and last I checked, they need one.
Second, the Christian worldview tells us that there is an objective standard of morality, and everybody has violated it. This is something that we all intuitively recognize. We all recognize that certain things really are moral abominations. While our moral senses may be skewed by society and conditioning, we still generally know that some things really are right and others really are wrong. But as I argued in my article Can Goodness Exist If God Does Not Exist? the naturalistic worldview has no ontological foundation for moral values or moral duties. That is why most secularists have adopted relative morality, which is to say that human beings more or less decide what is right and wrong. But we do not really have value. As the atheist Dr. Michael Ruse suggested, “Morality is a biological adaptation, no less than our hands and feet and teeth.” The problem of sin is minimized.
Yet nobody can live as though there was no sin in the world. Nobody can live as though all claims were morally neutral. We all cringe in disgust at the idea of the child molester. Nobody can say that this man is morally neutral. But the secularist is left to just throw up his hands in futility, as he is left unable to make that condemnation. As Bertrand Russell said, “Only upon a foundation of unyielding despair can the soul’s habitation be henceforth safely built.” The secular worldview makes no sense of the problem of sin. But the Christian worldview (informed by the Bible) does.
Of course, one may object that Christianity is not the only worldview that posits the existence of God as the ontological foundation for moral values and duties. But while all of these worldviews may say that God exists, they offer an inadequate representation of God’s character, for in all of them, sin is not dealt with. After all, as the atheists will ask, why is there so much evil and suffering in the world? Where is the God of justice? Why does his judgment and his wrath tarry? Why has he not destroyed the sinful man? The competing worldview will usually suggest that if our good deeds weigh more than our evil deeds, then God does not need to give them justice. He will have mercy on them. But this mercy comes at the expense of his justice. If justice is not truly executed, then God is like the unjust judge who took a bribe (good deeds) and let a guilty criminal go.
The Christian worldview resolves this dilemma. Paul wrote, “…Christ Jesus; whom God displayed publicly as a propitiation in His blood through faith. This was to demonstrate His righteousness, because in the forbearance of God He passed over the sins previously committed; for the demonstration, I say, of His righteousness at the present time, so that He would be just and the justifier of the one who has faith in Jesus.” (Romans 3:24b-26). We are guilty, and Jesus Christ paid our fine. He died in our place. How do I know that the Bible is God’s word? It is only by assuming the Christian worldview (informed by the Bible) that you can make sense of the world around you, including the existence of the universe and the problem of evil and suffering.
If you enjoyed this and would like to read similar content, see my article, What Does ‘Jesus Died For Our Sins’ Mean?