I believe I read your post. That was exactly my point though.
If it was irrelevant then, what is to say that some newer, equally ceremonial part (Baptism, say, having replaced circumcision, being replaced by something else, or even be dropped; you cannot save the souls of others simply by dipping their heads in water as newborns. They must accept Christ into their hearts) is not irrelevant now? My point is not that 'God says murder is bad', but that 'the Bible says X is bad, but perhaps it isn't really, because A. Bible was written by man, who is flawed, and keeping a text, even a holy one, accurate through the better part of two millenia, in multiple and changing languages, accurate for that long is...difficult; B. God changes His mind, apparently, as shown by the fact that the Old Testament and the New disagree at times; and C. I can only know, truly, in my heart(I won't speak for other people here), that I do good, when I do good that affects this life. If I do something which appears to be good, but the Bible disagrees, why is my moral intuition, granted by God, subservient to the fallacies of men a thousand years over? People change their mind on what the bible means, and different interpretations result in different translations, leaving out all the other things I said.
God's Word may be law, if I take that as my moral code, but the Bible is not His Word unfiltered and uncorrupted, as near I can tell.