According to the Bible the people who called themselves "The Way" were first called Christians in Antioch.
Ac 11:26 and when he had found him, he brought him unto Antioch. And it came to pass, that even for a whole year they were gathered together with the church, and taught much people, and that the disciples were called Christians first in Antioch.
And their leaders at the time was Peter as well as James in Jerusalem, very observant Jews, of the Nazarene sect. Thus, the BIBLICAL meaning of Christian, is a member of a Messianic sect of Jewish Nazarenes. At the time, Paul was completely under their ultimate authority, the split between the Jerusalem Church and Paul had not quite begun, so the ones in reference to whom "Christian" is used to refer to, in any objective sense, is clearly implying Peter's Church under his authority and rules at the time, which was very Jewish.
I would go so far to say that any attempt to render the initial Biblical meaning of Christian as other than a Nazarene under Peter's Antioch or James' Jerusalem Jewish Messianic sects is an attempt at furthering a history of intellectual dishonesty among Christiandom. It cannot be defended as meaning anything but Jewish Nazarenes, which was nothing close to the orthodox gentile system established after Paul.
And according to scriptures like Matthew 7:22-23, virtually everyone who is "Lawless", which in Matthew's terms would only apply to "Law of Moses" is going to suffer rejection at the day of Judgment. Additionally, those whose works are not hot enough but are luke warm will be spat out, one of the clearest indications of works-based salvation. Even Paul admits that Christians must "work out their salvation" with fear and trembling.
Whatever the meaning of Christian is, the scriptures when read plainly and not in a cherry picked arbitrary matter, clearly indicate that 99.9999999% of Christians are in fact, going to hell, by its own standard. Any attempt to argue against that will require virtually rewriting the context of what Jesus says, and attempting to negate and contradict even Paul who says that even unrepentant fornicators will not go to heaven. (Guess what part of the Christian population that makes up).
Going back to the OP, look at the Christian defenses at why Remarriage is justified, they basically say you can ignore Jesus's own words because he saves you in the end. At what point do they decide what they have to follow and what they don't?