Everything comes back to Jesus. It is all about Him. Fortunately, we have the most evidence for Jesus, His death, and His resurrection.
I have a simple logical argument that can be simplified in this equation:
Notably, this argument comes primarily from the mind and scholarship of Dr. Gary Habermas. His bookThe Historical Jesus, among many others is absolutely invaluable to apologetic efforts. I highly recommend his work. Lee Strobel is also a good author on the subject. His book The Case for Christ has helped many come to faith. I think you will find Strobel easier to start with. Habermas is a good next step.
There are 4 primary criteria that must be met for a first century historical document to be considered reliable:
- Number of copies (the more the better, at least 26)
- Few Variant Readings (the fewer contradictions between copies, the better)
- Date of Writing (the earlier, the better)
- Number of Sources (the more corroborating, the better)