originally posted by ToHoldNothing
One could start with the belief that Jesus is the core focus for attaining salvation and a relationship with "God"
Absolutely!
Then add specific things such as 1) Jesus died for our sins, 2) the Holy Spirit is divine, 3) The Father, Son, and Holy Spirit are not the same; each is God; and God is One; and 4) Jesus has a dual nature--of God and man.
Just those alone create a problems for many sects that claim to be Christian.
Heresy doesn't deny one the standing of being considered as part of a religion in the historical and general scholarly sense.
I do agree with you at least in part; but theologically speaking, we must actually look at the criteria within the Bible. Jesus and the Apostles tell us what the requirements are. In general terms, if one is not born again, he is not of God. The question becomes what determines who is born again. That is not always easy to determine by looking outwardly towards behavior. Even some people will answer yes to a series of questions but are far from being born again; but in general, we can tell upon closer examination. When looking at individual groups, their creeds become central to determining whether that group is Christian or not. The Nicaean Creed is a very good litmus test.
Otherwise we wouldn't still basically accept that even if the Orthodox, Catholics and Protestants call each other heretics or false Christians, that they are all Christians by a very particular common idea that I noted above
But, this has more to do with dogma than scripture. In general, both Protestants and Catholics agree to a minimum amount of requirements stipulated by the Bible and early Church creeds as do other orthodox Christians. We are saved by God's grace through faith in Jesus Christ. Faith in Christ is not just repeating some creed, but the internal acceptance of who Jesus is and what He did for our salvation and how He dealt with our sins. If they don't believed that Jesus saved us from our sins, then they are not Christians since they have no mind and will to accept Him. They have not confessed Christ as their savior. No Christ--no salvation--no Christian.
BUddhism is more fraught with difficulty because many insist it is more a philosophy than a religion, which can be a large divide of sorts in classification
But can one be a Buddhist and not accept Buddha? I am sure there are some set of minimal requirements to be a Buddhist. If not, then the door is open for many types of beliefs.
It's defined by what we extrapolate and draw from general texts. Canon or otherwise, even.
Exactly! Isn't there an agreed upon set of minimal requirements?
One difference in Christianity is that Salvation only come through Jesus; so, one way or another--no matter what differences one may have with another--no one can claim to be a Christian without accepting Christ and His salvific works. There is no way around it! The other stuff that we call differences, heretical, etc. doesn't matter at that point. Our foundation rests upon who we believe Christ to be. The Apostles make it quite clear who Christ is. Apostle Paul makes is very clear that any teaching of Christ different from what has been preached by the Apostles is not of Christ. We do have those teachings available to see and read.
I just admitted that, even including non Jews becoming Jews by conversion in the religious sense. Honestly, the same difficulty persists with those who have a Jewish identity and hold Christian beliefs and then the "Gentiles" that are converted from more "pagan" beliefs in the early history.
There were difficulties at the beginning, but they were worked out as we see from the various meetings undertaken by the early Apostles and Church elders along with the help of the Holy Spirit. Even some of the very early Church councils helped to shape understanding of who was a Christian. They did a lot of the ground work for us today.
I do agree with you about the difficulties that may be present in identification of groups, but we have criteria to separate the various sects from orthodoxy. The reality is that some sects are marginal and are not as easily to separate because they agree very closely with establish creeds, but deny something that may or may not be deemed as essential; however, denying Christ and His salvation is not one of those negotiable ones.