Revelation 12:11 “And they have conquered him by the blood of the Lamb and by the word of their testimony, for they loved not their lives even unto death.”  ESV

I have a mathematical card trick that makes me look like David Copperfield, but a five-year old could do it if they knew the secret.
So how do I know that the blood of the Lamb deal is real and not a trick?  
At nineteen, I got on my motorcycle and told God that I couldn’t believe in religion anymore.  What’s the difference between believing in Jesus, Buddha, or Mohammad I reasoned?
Then six months later a mathematician/engineer sat down with me on a bench and told me why he believed.  
He said, “You know, the Old Testament was written hundreds of years before Jesus walked this earth.”
“How do you even know Jesus was real?”
“History records, even by atheists, that Jesus physically walked this earth.”
“How can you prove he did all those miracles?”
“Well, there are over three hundred prophecies of the Christ in the Old Testament, before Jesus was ever born.  
Let’s just take eight prophecies…hung on a tree, where he was born, how he was born, etc.”
“Okay.”
“Eight prophecies fulfilled come out statistically ten to the seventeenth power.  That’s like filling the state of Texas two feet deep with silver dollars and a blind man picking the one and only silver dollar that is marked.  Do you realize the Old Testament said he’d be hung on a tree hundreds of years before the Persians invented crucifixion?”
“Really?”
“Jesus fulfills over three hundred prophecies bud.  I can’t even give you a mathematical picture of what that looks like.  
History, archaeology, math, and science all testify to the reality and truth to the gospel.”
We have over three hundred reasons to believe that Jesus is the Lamb that takes away all our
sin.  That’s a deal, no tricks.