What does it mean to count the blood of Christ ‘an unholy thing’? Well the word translated ‘unholy’ could be translated ‘common’: a common thing, a non-sacred thing. So a person could be guilty of counting the blood of Christ an unholy thing just by saying, ‘I regard that as nothing.’ If you were to challenge them, ‘Oh but you have said something terrible. Doesn't it concern you as a Christian? Don’t you have any regrets about saying that, any conscience about it? Are you not counting the blood of Christ an unholy thing?’, and they replied, ‘Oh don’t appeal to me along those lines; that is nothing to me’ then they are esteeming the blood of Christ as a common thing, something of no special significance. So this is an error that people can fall into as worshippers if they have never been truly converted.
Some people say that verse 29 is an authority for teaching that there are different levels of punishment in hell, but it does not necessarily establish that. It is expressing things in very human terms. Even in human reasoning, the writer says, you can see that to reject Jesus Christ who is the reality is a more serious step than rejecting the shadow that came in the law of Moses. And yet even those living in the time of types and shadows were punished. How much more those who despise the gospel. We have to be careful what we use as a proof text to any point of view. However is it certainly true that increased light brings increased responsibility before God.
Look at these words ‘and hath counted the blood of the covenant wherewith he was sanctified, an unholy thing.’ Of course if the person is a false convert he was never really sanctified. So to explain the verse, many interpreters say that ‘he was sanctified’ applies to Christ, not the false converts. So they like to read the verse that way, but I am sure many of you would be concerned about it. It may well refer to the false convert, but not in a real sense. We might insert the words to clarify the meaning: ‘he has trodden underfoot, the Son of God and have counted the blood of the covenant wherewith (he claimed) he was sanctified, an unholy thing’.