Deliberately misleading argumentation; the actual answer is that Mt. 5.17-18 brings the whole of the Law, including the parts about who to kill, what to cut off, and when to poison your wife, to the Christian Scriptures. There is, of course, plenty to argue within that framework, but maybe that's too subtle a discourse for you to comprehend.
Is the so called prophet Muhammad an " Islamic authority"?
Think very carefully about what you think you're doing and what you're about to do. You've already been called out on misrepresenting Qur'an and ahadith, and your retort on this occasion is, technically,
non sequitur.
Yes a very ancient scripture written for the Hebrew /Israelite audience of the time, (doubtful if any of them could even read) and not really adhered to by Israelis or Christians in the 21st century.
Are you, then, ranging into argumentative hypocrisy, or simply not thinking through the implications of your gasp and grab straw job? The thing is, there are plenty of discussions to be engaged, but you just can't seem to find any; part of the problem might be your priorities. Actually learning and having a clue is not inherently part of being a bigot, and, indeed, most days seems rather quite antithetical. And it's not so much that you're welcome to prove that point all you want; people already get the gist of it, and this is the sort of thing they weary of.
No, really, for one who considers himself "pretty well read on the Christian religion", you're rather quite not. To the other, a multistate effort to organize votes to legalize the murder of homosexuals setting off a high-profile political and legal dispute that runs a quarter-century before losing outright, is the kind of subtlety that escapes many.
It's like a weird moment after the Pulse massacre in Orlando; a preacher in California went off about rounding up all the gays for a firing squad to blow their brains out, and while everyone was gasping horror and stepping up to the line to stand with their queer neighbors, Sen. Ted Cruz (R-TX), a known homoophobic bigot, turns up trying to convince the LGBTQ+ community that he is and always has been their friend, and thus they should hop on his anti-Islamic bandwagon, and now more than ever. We might wonder: Is Ted Cruz really that stupid, or does he think homosexuals are? (For the record, the most reliable answer is to remind that the conditions are not mutually exclusive.)
Steve Benen↱ went ahead and formulated the stupidity:
What Cruz doesn't seem to appreciate is the fact that the LGBT community and its allies already know that radicalized loons hate gay people—just as we know Ted Cruz pals around with Christian extremists who believe Scripture demands the death penalty for homosexuality.
The enemy of an enemy is not necessarily a friend: When the guy who kowtows to the murderlusting homophobic Christian tells gay people they're on his side, homosexuals know better. The thing is, it's not just homophobia; that a bigot might show bigotry against another who is bigoted against yet someone else does not make the one bigot a friend of that someone else.
Empowering bigotry is empowering bigotry; that one is not the target of whatever hatred happens to be fouling the room in the moment does not change this point. When the anti-Muslim bigot appeals to homosexuals for support, many of those homosexuals will notice the fact of bigotry. If homosexuals support your manner of anti-Islamic bigotry, they empower anti-gay bigotry such as we've seen from the Texas junior and his murderlusting Christianist associates.
And we can believe that's all too subtle for someone as well read as you pretend to be, if you really need so low a bar, or we might wonder how stupid you think your audience is.
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Notes:
Benen, Steve. "Cruz sees Orlando massacre as possible wedge issue". msnbc. 13 June 2016. msnbc.com. 30 June 2016. http://on.msnbc.com/25T6qFt