Christian "purpose" and "meaning" in life.

[Godscreated]

Till you get to the atheist part I can accept those things, I can check those out. However how am I suppose to check out what you feel, by your actions and speech. Atheist tell Christians we can't tell whither an person is a Christian or not, we say we can by their speech and actions, but that doesn't seem acceptable to atheist, so why should I grant your claim to be an atheist by your actions and speech, as you note below.

I think the difference is that we would judge a person as being atheist or not based on a single criteria: do they believe in god(s).

That would be a reasonable criteria, but how can you prove one actually holds to that belief, there are no requirements for non-belief, other than one says so. How do you prove something that's void of facts and anything tangible.

There can probably be areas of quibbling, but that's the gist of it. We see Christians from various denominations claim that other self-identified Christians are not Christians at all, and those will make the same claim right back.

I do not do that to any denominations as a whole except the Mormons and JW, there doctrine actually changes parts of the Bible, they add to Christianity things not possible according to scripture. I have problems with some of the Catholic Church doctrines, however I know Catholics I believe I will see in heaven.
The infighting among the denominations is one of the greatest harms to Christianity, it's existed nearly from the beginning and I suspect it will go to the end, unfortunately.

Some people claim to be Christian but not members of any particular religion, using the Bible as their guide and avoiding any other affiliation. Nearly every Christian that I've seen, regardless of denomination, could reference scripture to explain why they were true followers of Christ and why others were not.

I think you're exaggerating a bit, most Christians accept other denomination, there are disagreement but few doubt each other are Christians. Yes there are some denominations that set themselves above all others and claim they are the only real Christians, they think more of themselves than the One they are to serve. What's wrong with those who decide to live in a relationship with Christ apart from a denomination, seems to me they are trying to live a life for Christ without the distraction of infighting, could be they base their beliefs on love. Something many Christians could have in their lives, including me.

For JWs and Mormons (and similar groups) it seems easy to disqualify them, as they have either added to scripture or modified it to support discordant beliefs. But most Christian denominations only use the Bible and so the differences between them is down to interpretation. Your stated view that a person's devotion to Christ is more important than any affiliation is the most sensible one to me, but probably not to other Christians and faiths.

It's good to see a non-believer who actually tries to understand Christianity and what goes on within the denominations.
Yes, it does get down to interpretation, unfortunately most interpretation comes down to self desire in this day and time, I'm not sure of the intent of the originators of the denomination, I will err to the side of honest intent.

It's not that I don't think you are a Christian, but that so many Christians seem to assume the authority to deny the legitimacy of others, and vice-versa.

I'm only going to look at individuals actions and their speech to make a determination of their claim of Christianity, I believe we are allowed that to protect the church, I see it as a responsibility of Christians to the church and scriptural at that, we should never abuse this right out of personal feelings.

GC