JP-
Whilst i do disagree with your idea that people can't come up with a system of right and wrong on their own, even if this was the case the theist position is no better. The fact that the author of the article points out that there are Christians who "have misunderstood and misapplied this stewardship" clearly shows that people disagree even when they are told what to do in whichever ancient book they happen to choose. Can you tell me which version of the Christian faith is the correct one? Or which Religion in general? You can try but not many will agree with you.
It get worse when you actually read these books and start to realise the kind of world they actually do promote, as pointed out by other comments.
It seems pretty obvious to me that the moral compass of each individual is both affected by the society they are brought up in (parents, friends, school, government and religion if any) and the individual themselves. But just because everyone's compass isn't perfect doesn't mean that there is not a direction we should all be heading based on the evidence of what benefits us as humans.

JP,

If your source of morality is so objective, then tell me: by what method or mechanism do you determine that God is the one that is good and Satan is the evil one?

How do you know that you're following the right one, and that Satan isn't sitting around waiting for you to realise that what God has been saying isn't good at all?

At least Satan is more mature than God. Here's God, bagging out Satan like a school kid, and all the while Satan just sits back and rises above it all by not returning in kind. 

Jokes aside though, JP, my questions above highlight the glaring oversight in your logic.

Oh dear another "them bad atheists and how only someone with faith in the un provable can believe in a future". Seriously Robert Martin that article is just self indulgent drivel dressed up in a thing veil of pseudo intellectual goop.

Atheism is only a position that one has no belief in a (any) god or supernatural, it is has zero to do with anything else a person may consider or even hold important to their lives. Indeed you may be conflating atheism with the biggest impediment to climate change and the earth, religion.

JP,

(1) "no one denies that atheists cannot and do not make up their own notions of what is right and wrong and then call this “morality”. The problem for atheists is, what to do when atheists disagree with each other about what behaviours to call right and wrong"

As NathanF has commented, this is precisely what Christians and other theists do, and have done for millennia, and the result is often bloodshed on an enormous scale. Why didn't the deity make his/her/its message clearer? Christians, even amongst themselves cannot agree on the "word of God", there is really no universal Christian morality.

(2) You haven't answered my question as to why the interpretation of the Bible has changed throughout history--the most plausible answer is that the continual re-interpretation is due to cultural change and the resultant different mores. The Old Testament God urged his followers to invade Canaan and massacre its inhabitants, do you agree with that as a moral imperative? What is your opinion on the ethics of the institution of slavery or chattel status for women and girls?

(3) Then there's the problem of theodicy, how can the Christian God exist?

Both Christian and atheist morality are the products of the human mind, unfortunately only atheists understand.

AJPhillips,

Yes! Of course! There are two gods, one good, one evil, and the evil one created the world and wrote the Bible, the Gnostics were right!

Let’s assume that everyone has come to the conclusion that atheism is true. So now, instead of attacking theists that is no longer necessary because no one believes in God.

That being the case though, everyone would still have the problem of not being able to sort out who is right or wrong on moral issues. The rainforest destroyer could claim that in his opinion he had done nothing wrong while others could claim that he had. But no one would have any basis for saying whether he or anyone else was correct about that.

NathanF, it appears that you would want to say that we should act in ways “based on the evidence of what benefits us as humans”. But that is just your particular preference. Another person may prefer to act in ways that benefit just themselves without any concern for anyone else. Yet another person may preference the well-being of great apes over human beings. These different preferences may come into conflict and in atheistic universe there is absolutely no way of determining which preference should prevail.

oh dear some more of that Christ-stain compasion on show agian.
2000 years to come up with some actual proof:- fail.
2000 years to get your sorties straight:- fail.
2000 years of peace in christidom :- err mega fail.
should i go on as with most Christ-stainers his "beliefs" are there merely to provide him with a sense of the high moral ground from which to sling his....