I don't usually talk Christian Theology on my blog, but today I'll make an exception.
According to the Bible, Christians are supposed to TRY REAL HARD not to sin, but if we fail, the blood of Christ is sufficient to cover those sins, and we just ask for forgiveness and help not sinning any more, and then carry on.
However, there is one unforgiveable sin, that is, blasphemy against the Holy Spirit. There's a lot of debate in the Church at large about what, exactly, that means. I don't know for sure, but I'm pretty sure it's when you fail to clean up your dog's shit when you're walking them in other people's yards.
Kidnapping Jesus and holding him for ransom is forgiveable.