Thank you for being honest. So, if murder is wrong because God says it is wrong, then it would follow if he were to declare it right it would be right, yes?
Theoretically. But God has always said it was wrong, Old Testament and New. See the murder vs killing thing above for the warfare explanation.
So it's kind of an if my uncle was my aunt proposition. Yes, ultimately you need to do what God wants you to do. But God in the Bible has already said he is not changing moral laws. What he changed in the New Testament were ritualistic laws (like the dietary restrictions) and the ultimate penalty for breaking the moral laws. But Jesus was very clear that the moral laws still apply, and he summed them up with the Golden Rule.