Let’s consider this statement. (I’m not offended - it is pretty common and you seem ready and able to defend it.)
Let’s look at it historically, then logically. Historically, unless you are a literalist who believes in Adam and Eve and the Garden, you have to admit that morality existed long before the concept of a Western God did. They Egyptians had moral rules, as did the Babylonians. Indians, Chinese, all had moral rules without ever hearing about our God. Now, if these rules were revealed by our God, how come he didn’t reveal himself in the same manner he did to Israel? If not, where did their morals come from? Further, we could go back to prehistory and expect that a lot of morality existed then also. And, did the Aztecs get just a bit of morality, and the part about not ripping out your enemies hearts get left out?
Isn’t it more likely that morality evolved along with us, since a group without any morality would not last long? If morality is in our genes, we could expect natural genetic variance to produce immoral and amoral people, and that is exactly what we see.
Now, the logical part. If morality comes from God, then there are two choices. First, whatever God says is moral by definition. Second, God transmits to us a natural morality which he might be able to see directly but we can’t. In the second case, morality doesn’t really come from god at all. In the first, how can we tell if a command to do what seems to be evil comes from god or not? Consider God’s command to Moses to slaughter the tribe in their way. Was that a moral thing to do? Today we’d say know, but you’d have to call it moral coming from God. As our morals evolve past such things, we have to call ourselves more moral than God. It doesn’t matter if the story is true or not - the principle remains.
Another logical issue is this: anyone taking an ethics class runs across many cases where simplistic morals don’t work. Stealing bread for a starving child is an example. If morals incompass these cases, then God’s moral code must consist of not 10 or 100 commandments, but specific answers to every situation. Without direct access to God for advice, it is hard to determine what is moral in a situation. Gay rights is an example here, and many religious gay people can’t accept that God considers the core of their being immoral. They say that true morality contradicts what the Bible says directly (and they find indirect justification) and no doubt believe that if God spoke he’d agree with them. I think any God worthy of worship would myself. I’m hard pressed to find any moral arguments against their position (except god says its wrong, so there!) and I wonder how you justify it - one way or another.
I know someone who says that morals are religion based, and there is no such thing - only ethics, which is derived by reason. I’m partial to this view.