It's not 'Christians' who are supposed to give to the poor - it's 'everyone'.
It's not 'Christians' who are supposed to tell the truth - it's 'everyone'.
Lying, cheating, stealing, adultery, abortion, sodomy... take your pick. As far as Christian teaching goes, these are not moral oughts 'for Christians'. They are moral oughts for everyone. Being a non-Christian doesn't mean you operate by a different set of moral rules.
The idea that Christian morality only applies to Christians isn't a biblical teaching. That's just a case of people confusing a secular "separation of Church and State" with Christianity itself.
There's a lot to say here, but I want to zero in on one thing in particular: when I catch people, particularly other self-described Christians, insisting on harsh standards of morality for Christians - but who are absolutely, positively loathe to suggest these standards for anyone BUT Christians, much less hold others to them - I don't just see someone making a minor error. In fact, I see something much more than an 'error'.
I see abuse. Straight up psychological abuse. And I see it being used against a group of people who have been abused quite enough during this and the last century, thank you. And I'm not going to tolerate it, because I consider tolerating it to be immoral.
It doesn't matter if you're all smiles with me. It doesn't matter if you plead to high heavens that you love your Lord Jesus Christ, Son of God, yadda yadda, with all your heart. When you start talking about how Christians should gleefully surrender themselves to torment and execution (and indeed, that suggesting otherwise is unChristian and sinful and you're a bad person for suggesting that people, you know, have a right or even a duty to defend themselves and others), I'm probably going to just call you a moral monster and tell you to fuck off.
Because, hot on the heels of a century where Christians were put to death en masse, in a world where the culture at large is hostile to Christianity and heaps emotional abuse on them at the earliest moments, you're going that extra mile and justifying it all. I regard you with the same emotional response as I would some decrepit old fuck of a priest telling a teenage boy to just accept his molestation or Jesus will frown at him.
And if you tell me 'Don't find malice where stupidity or ignorance may be the cause!', don't worry - I assure you, I'm considering all three of those options when I evaluate you.