Christians have a lot to be worried about on their death beds.
Mark 3:28-29:
"Truly I tell you, people can be forgiven all their sins and every slander they utter, but whoever blasphemes against the Holy Spirit will never be forgiven; they are guilty of an eternal sin."
There are literally dozens of interpretations being circulated as to what this "UNFORGIVEABLE SIN" exactly involves. Not knowing its precise definition has generated real terror among many devout Christians.
Since there is no precise definition, a Christian does not know whether or not he/she has committed "the UNFORGIVEABLE SIN " yet, if a Christian commits this sin, they can never be forgiven. They will spend eternity in the torture chambers of Hell.
Many Christians live in fear as they do not know whether or not they have committed "the UNFORGIVEABLE SIN ".