There are millions of Christians like this in the US alone, let alone the rest of the world. I'm not sure what you're trying to push with your interpretation of christianity, but it's certainly not common, given that it assumes their god doesn't exist.
It’s hard to imagine who Augustine wrote his Confessions to or on whose behalf Galileo was killed, if all these people were just talking about metaphors.
If you built a power structure on top of a religion, or if you think that preserving respect to certain ideas leads to a more harmonious society in general, you can very easily prosecute people that undermine them, whether you believe them as real or not.
What I'm getting at is that it doesn't have to assume their god doesn't exist, as this is a negligible detail (implementation detail) on the respective worldview and its results in everyday life, culture, etc (not in the coarse grained debates in the US 15th-21th centuries, but in the course of 2 millennia of European and global history).
I'm skeptical that throughout the history of Christianity, everyone took the "parable" interpretation of the bible (rather than taking most or all of it seriously). Are you claiming that the... inquisitors (?) weren't killing based on a literal lack of belief in god, but rather were killing because people weren't morally up to snuff? I'd love to be educated here, theology and the history thereof are well out of my wheel house.
Personally, it seems reasonable that "Jesus" was a Joseph Smith type of con man who managed to spin yarns and somehow create a following.
Here is a passage from a truly fascinating Christian author from the 2nd century. He starts by saying "we shall be told that these are fictions, no better than fables, like the rest of the strange stories about Jesus." (funny how arguments against Christianity haven't changed for 2000 years)
Origen's reply is this:
Our answer is that to reconstruct almost any historical scene, even if true, so as to give a vivid impression of what actually occurred, is exceedingly difficult, and sometimes impossible. Suppose some one to assert that there never was a Trojan war, mainly on the ground that the impossible story of a certain Achilles being the son of a sea goddess Thetis and a man Peleus is mixed up with it; or that Sarpedon was the son of Zeus, or Ascalaphus and Ialmenus sons of Ares; or that Aeneas was Aphrodite's son: how could we dispose of such an objection? Should we not be very hard pressed to explain the strange blending of a fiction with the universal |74 belief that there was war between Greeks and Trojans at Troy? Or let us suppose some one to doubt the story of Oedipus and Jocaste, and of their sons Eteocles and Polynices, because that a sort of half-woman, the Sphinx, is mixed up with the story; how should we clear up the difficulty? Well, the prudent reader of the narratives, who wishes to guard against deception, will use his own judgment as to what he will allow to be historical, and what he will regard as figurative; he will try to discover what the writers meant by inventing such stories; and to some things he will refuse his assent on the ground that they were recorded to gratify certain persons. And this we have premised, having in view the history of Jesus as a whole contained in the Gospels; for we do not invite intelligent readers to a bare unreasoning faith, but we wish to show that future readers will have to exercise prudence, and make careful inquiry, and, so to speak, penetrate the very heart of the writers, if the exact purport of every passage is to be discovered. -- Philokalia of Origen CHAP. XV. 15
The inquisition were killing for many reasons (and not as much killing as its mythologized), but most of them were political. See for example: https://en.wikipedia.org/wiki/Historical_revision_of_the_Inq...
Christian refers to billions of people through 2 millennia, and their approach to religion and belief is far more nuanced than what stupid fundamentalists (which is a newish invention) have.
The key is that there are no "rules that he himself also put in place" etc. (as he doesn't exist and even if he did it wouldn't matter). The rules were formed by people (obviously) and codify societal practices and philosophies towards morality and right. The story of Christ, as such, codifies a different approach contrary to those older practices -- which is why it was the basis on a whole different mentality that shaped Europe and ended in things like the "human rights" and modern ethics.
(Or course this can be difficult to fathom in places were Old Testament beliefs are still championed, along with very crude literal meanings of religion, in the name of "Christianity". But this wasn't the case in later Rome and Europe, not even in the Inquisition era).