Among my friends and colleagues, most assume there is little or no evidence for the Christian faith. They might say that Christianity has some comforting ideas, but they probably wouldn’t think it was intellectually credible.
I can understand this reaction. After all, the Christian religion makes some pretty spectacular claims. Christians believe that Jesus imparted world-changing wisdom, healed the sick and raised the dead. Furthermore, after dying on behalf of humankind, three days later he was resurrected (i.e. he came back to life) and eventually ascended to heaven. In a context where many of us default to a scientific naturalism, the ‘spiritual’ claims of miraculous healings and Jesus rising from the dead seem too incredible to be true.
And yet Christians understand the gospel accounts not as imagined spiritual myths, but as reports of genuine historical events. As with any historical claim, they need to be evaluated against the evidence. Coming from a Jewish/atheist family background, I spent time investigating the evidence whilst I was at school and university. However improbable, I came to the conclusion that Jesus was no mere man. So, what was the historical evidence that convinced me?
1. Roman and Jewish historical evidence
Even when you ignore the biblical testimony, we have compelling evidence for Jesus’ existence from the leading non-Christian historians of the era. Tacitus, generally recognised as one of the finest Roman historians of the first and second centuries, and Josephus, one of the most significant Jewish historians at the time, both record evidence of Jesus’ existence.
Tacitus mentions a group known as Christians, named after Jesus Christ, living in Rome in AD 64:
Nero … inflicted the most exquisite tortures on a class hated for their abominations, called Christians by the populace. Christus, from whom the name had its origin, suffered the extreme penalty during the reign of Tiberius at the hands of one of our Procurators, Pontus Pilate… 
The ‘extreme penalty’ he describes matches with how a Roman would have described Jesus’ crucifixion and death, under Pontus Pilate’s instructions, who is also described in the biblical accounts.
The non-biblical evidence is so convincing that almost no historian questions Jesus’ existence. Agnostic scholar Bart Ehrman says,
The reality is that every single author who mentions Jesus – pagan, Christian or Jewish—was fully convinced that he at least lived. Even the enemies of the Jesus movement thought so…Jesus certainly existed. 
2. Historical credibility of the New Testament
It’s often suggested that the New Testament accounts can’t be trusted because we only have copies of copies of copies translated many times over. Or that they were written hundreds of years after the event, so they can’t possibly be considered credible historical sources.
Actually, the opposite is true.
The gospel accounts are generally accepted (even by many non-Christian theologians) to have been written within the lifetime of Jesus’s first followers, likely within 50 years of Jesus’ death (i.e. circa 80 AD), which fits with their claim to be based on eyewitness testimony .
Our first manuscripts date from a very short time after the originals. The earliest manuscripts were produced in the early second century (circa 125 AD ). This gap of 40-50 years between publication and copy is almost unheard of in comparison to any other classical literature. For example, Tacitus wrote in the 1st century, but the first copies we have of his work date from the 9th and 11th centuries: a gap of 800 years.
FF Bruce, former theology professor at Manchester University, said, ‘there is no body of ancient literature in the world which enjoys such a wealth of textual attestation as the New Testament’ . We can be confident that the gospels we hold today are essentially identical to the originals written nearly 2000 years ago.
3. The Gospels as eyewitness testimony
Not only can we date the gospels to within the lifetime of Jesus’ followers, but in them there are a number of clear pointers to the fact that these are authentic eyewitness accounts.
For example, the gospel writers mention real people who would have been known to some of their readers (who presumably could have spoken out if the gospel accounts were inaccurate). In the 15th chapter of Mark’s Gospel, Mark mentions Simon of Cyrene, ‘the father of Alexander and Rufus’. There’s no reason in the narrative to identify Simon’s children. Commentators believe that he’s referencing Alexander and Rufus as if to say, ‘if you don’t believe me, speak to them, as they know their father was there at the time’ . The gospels are willing to identify real people who were there at the time. This is no ‘fake’ account written hundreds of years later.
4. Jesus’ resurrection
All of this evidence is worthless, though, if it was just evidence that a good teacher once lived. It only matters if he was who he said he was—God in human form. For me, the most convincing proof of this is the resurrection. The sheer improbability of the event (dead men don’t rise) means that if it did happen, then surely he couldn’t just be a man.
What’s the evidence for the resurrection? Two key facts stand out—the fact that the disciples were willing to die for what they believed in, and the rapid growth of the early church.
The disciples claimed to have witnessed Jesus alive after he was resurrected. Many of them would go on to die for this claim. Of course, many people will die for what they believe, but no one will die for something if they know it’s not true. So, their willing death (at the hands of Roman or Jewish opponents), means they definitely believed that Jesus had been resurrected.
Could it not have been a collective hallucination? No. That kind of thing just doesn’t happen—there are no recorded instances of hundreds of people seeing the same thing at the same time .
5. The explosive growth of the early church
The resurrection is the only fact that makes sense of the growth of the early church. In the period before and after Jesus’ life, there were many ‘messianic movements’ in Israel. However, when the leader of a movement died, the movement would collapse. But Jesus’ movement follows the opposite pattern. After his death, thousands of people chose to follow him, and Christianity exploded across the Roman Empire (despite the fact that following Jesus was illegal and could result in death). Why is the Jesus movement the exception to rule? What led the disciples out on their mission to tell others about Christ despite facing huge opposition?
The only way any of this makes sense is that Jesus was actually resurrected, that the disciples saw it and were convinced and were willing to die for that fact.
Manhattan pastor Tim Keller writes,
The resurrection of Jesus is a historical fact much more fully attested to than most other events of ancient history we take for granted. Every effort to account for the birth of the church apart from Jesus’ resurrection flies in the face of what we know about first century history and culture. 
Given the weight of evidence, I’m convinced it’s impossible that Christianity is just a big hoax. This man clearly existed and there is compelling evidence he was no mere man. However unlikely, the evidence persuades me he’s actually God in the flesh. When I came to that conclusion, it transformed my life. What might it do to yours?