Easy comebacks ?

[mordant]

Most Christians believe in the Old Testament, but not all of them in the same way, and not as a set of laws that are binding on them. 

Then they're hardly proper Christians, are they?

Boru

Not in the view of fundamentalists. As a former fundie, I still tend to have a bit of trouble seeing liberal Christians as "real" Christians. But they are not a monolith. And evangelicals, much less fundies, are a minority. A significant minority with an outsize influence in some places, but a minority just the same.

My estimate is that at least two-thirds of self-styled, "cultural" Christians do not take their religion literally or hold all that fast to it, have not read much of the Bible or studied it in any significant way. They allow it to be a general influence, but mostly live according to common sense like the rest of us. Which is to say, a mixture of quasi-objective, semi-intellectual, sloppy, inconsistent and emotionally tainted thinking. But nevertheless they function well enough to hold down a job and pay taxes and largely keep out of trouble with their fellow man.

We fundamentalists used to decry that two-thirds as "Easter and Christmas Christians" or "cafeteria Christians" or "baptize them, marry them and bury them" Christians. I even heard them referred to dismissively as "our weaker brothers in Christ". The only use we had for them (especially the Catholics!) was when we needed their numbers to bolster our argument that the capital-C Church was triumphant in the world (even then apparently what "triumphant" looks like, is only a third of the world on-board after 2,000 years of promoting the value proposition).

Christianity is a pretty big tent, encompassing countless hermeneutical systems that produces everything from Catholicism to Calvinism to Arminianism to Pentecostalism / holiness and each of those have a range of conflicting dogma (e.g., does one baptize infants, or adults only? By sprinkling or partial or total immersion?).

It is absolutely true that most Christians regard some aspect of the scripture as "not for today". The Old Testament is generally regarded as superseded by the New Testament, and as a source of general moral instruction but that today we are free from the letter of the Law. It is true that some cherry pick differently (e.g. whether homosexuality is sinful or not). Some fundamentalists say that one should expect miraculous signs and wonders from god, some say that is "not for today". Etc.