Religion says that God is the reason morality, as in justice and love, exists.  So if you say there is no God you may be moral but you have no reason to believe in being moral.

We are going to evaluate that argument.

Moral arguments for God incorrectly assume that God: Morality is all that matters or comes first

The argument is only for hypocrites. Rather than godly, the argument is an idol. God is an idol for believers need the argument and its lies in order to imagine they believe.
Believer - if there is no God then everything is permitted - if people did not believe in a God who values only the right things they would not have any reason to be moral. Not having God to decide or discover what is moral means you will end up with a DIY moral code. It will be self-interested, inconsistent, fluid and subjective at best. And even then it is still bad and potentially even more deadly.

Questioner - It could be that if there is a God everything is still permitted! Or at least permitted more than it would be if there were no God.  This shows that morality is not as important as we say even if there is a God.
Self-love is the thing that has to be there for morality to be even possible. Unless you love yourself you cannot consider morality important. How can you be moral if you hate yourself so much that you think it is okay for people to hit and abuse you? And that by implication insults other people too for you say they can be the same as you if they want to be. Self love cannot be an obligation or commanded. It cannot be a moral requirement for it has to be totally free and done because it is beautiful not because it is commanded. You cannot command somebody to enjoy their coffee for that defeats the purpose. Thus the persons who love themselves is doing something far more important than morality. Thus those who argue that morality in the form of God alone matters or is supreme in importance are doing you moral and psychological harm.

The Moral Argument for God

Who gets to decide if something is moral, immoral or neither (neutral)? Man or God? Or neither?

One way to state the moral argument for God is that to be a consistent atheist or sceptic about God, one must affirm that the child abusers and terrorists of this world do not really do anything 'wrong'. If there is no God then there is no objective truth about the good and the bad - there is only opinion about what is right or wrong.  

But look at that carefully. Belief in a God who grounds or is the source of objective morality does nothing to stop the problem in practice. If it deals with it then deals with it in theory only not in action or practice. If God is the mathematician that does not necessarily mean that man can do maths as well. Maths then would only be any good to God personally but no good to anybody else and everybody else has to make do with opinions about calculations. One person thinks 2 and 2 is 4.5 and another thinks its something else.

If all we have is opinions about good and bad, then we are still saying that good and bad are real. If you have opinions about the weather it does not follow that you think the weather is whatever you want it to be or think it is. No the opposite follows. You are searching for objective truth about the weather - it might be in the wrong way but you are searching. If good and bad are opinions or feelings they are still attempts to find objective moral truth.

Trying to ground morality in God is trying to get away from the fact that we are stuck with objective morality whether we have a faith in God or not. It is denying that it comes from us not God. The moral sense or faculty is there involuntarily and what we do with it is up to us.  Morality if it is based on love and justice asks to be freely embraced.  But that is not what we have.  We have something that in an undignified fashion we have, we just have it.  Thus in that sense morality is not of supreme importance but is a necessary evil in how it involves force.

Deep down, people know all that but they don't trust others with morality and suspect their perception of objective morality can be skewed and twisted. So they hope to bring God into it to manipulate people to have largely the same view and approach to morality. If you take your morals from your version of God and other people follow that version that should open the door to people being in agreement.

Real morality is about the intrinsic value of the person - it does not matter if you believe in God or not. You will value and that is all that counts. You cannot avoid doing it. Trying to say human value has to come from faith is just bigoted and in fact downgrading the human being even if it does not look that way.

If moral value of an action comes from outside it then it is not intrinsic to the act. God has to force the act of hitting a baby for fun to be wrong. But will that work? No - if it is not wrong cannot really be made wrong. And a morality that is about forcing and punishing in that way is gibberish. Human nature does not want a morality that forces.
Do not try to ground morality in God for it cannot be done. The God-belief is a danger to our standards of right and wrong. It is an intrinsic danger - and it has bad results too. Those who say it is essential to believe in God before one can believe in any of these standards are lying for there is nothing on this page that hasn’t been constantly said to the Church by its critics over the centuries. Belief in God is bad for us therefore to promote the belief is bad.
If good is independent of belief in God then no big deal should be made of God by believers. It would mean that good is good whether there is a God or not. We have enough trouble trying to work out right and wrong without religion adding to the difficulties and making a laughing stock of our efforts. And what about the wars over religion and how God is to be served?

If your value is to feed the poor that is good. If it won't become your value unless you believe in a God who commands it then there is something wrong.

You shouldn't need a belief as a crutch to give you the value. It means you don't value it at all but have to find a way to imagine that you do. What happens when the scales fall off your eyes? The belief is made more important than the value. Yet reason says a belief cannot be more important than liking to help the poor.

So we see what is happening is believers in God are reasoning, "Morality is all that matters in the end.  God is that which matters and must matter to us totally.  Therefore God and morality can be treated as virtually the same."  This does not work and a vicious circle like that is really just a lie so whatever it gives us it is not morality.
Handbook of Christian Apologetics, Peter Kreeft and Ronald Tacelli, Monarch Publications, East Sussex, 1995
The Future of Atheism, Alister McGrath and Daniel Dennett, Robert B Stewart, SPCK, London , 2008
Ethics: The Fundamentals, Julia Driver, Blackwell Publishing, Oxford, 2007