Standards that have been with us for thousands of years, both within religious contexts and without. Do you honestly believe that before Christianity - or before Judaism, for that matter - the ideas set forth formally in the Ten Commandments (among others) were completely alien to humanity? Pre-Judaic cultures were well aware that lying, cheating, stealing, not keeping one's word, etc. ..were WRONG, and they didn't need a formal, monotheistic religion to confirm this for them. And in today's world, atheists are no more or less likely to act unethically than people who are formal members of a religion.
Ask your atheist friends why killing children is morally wrong.
Completely alien? No, there is some vague sense and memory of divine image in every man. But alien in parctical sense, YES.
Now, to demonstrate it to you, no complex reasoning is need, but only simple facts generally known. Have a look at the societies like pagan Rome or Greece. In Greece it was considered a virtue to kill handicapped children. In pagan Rome the intelectual, moral, political and spritual elite was enjoying the circus where slaves were killed in ingenious and various ways to give pleasure and esthetic satisfactions. The general population and elite was enjoying this spectacle publicaly without any scruples.
This innocent enjoyment was spoiled later by "narrow minded" Christians, who brought the new awarness or gentle light of Gospel. It is true that the enjoyment of cruelty remained and pagan vices or false virtues persisted, but they went underground, covered with shame and hypocrisy.
Or see the example of Aztecs who saw it a virtue to practice their rituals (BTW the reason why few Spaniards so easily defeated a large Aztec empire, was that subjected Indian tribes preferred them over previous rulers).
Pre-Judaic cultures were well aware that lying, cheating, stealing, not keeping one's word, etc. ..were WRONG, and they didn't need a formal, monotheistic religion to confirm this for them.
Hmm, not really, in many cultures robbing and deceiving the strangers was seen as a good thing.
And in today's world, atheists are no more or less likely to act unethically than people who are formal members of a religion.
Well, let us not be blind to the facts. The first atheist state - Soviet Union falsified your claim. The first neo-pagan, post-Christian state Germany also was very revealing.
Well, well... Let's take a look at these "pre-judaic" peoples...
Genesis "6:1 Now it came about, when men began to multiply on the face of the land, and daughters were born to them," ... 6:5 Then the LORD saw that the wickedness of man was great on the earth, and that every intent of the thoughts of his heart was only evil continually.
Wow, looks like we have a bunch of natural born "do-gooders". LOL!
Name one person who kept the law flawlessly. (Hint, his Bd is coming up).