morality comes from God
period!
OK, so to actually build out your argument for you to show you how it works and what it means, you have a few places to go:
1. God works through determinism, such that our current views of morality as set out in how we interpret what God has told us was what God wanted, and God caused events to unfold such that religions that align with his view of morality have triumphed in our part of the world over less moral religions with different views (like paganism), while other religions in other parts we don't like and view as less moral are there to test us.
This view has all different sorts of implications for free agency, personal responsibility and the dehumanization of people who have different religions (and therefore is seemingly immoral on that basis).
It sets op violent conflicts between civilizations, and within civilizations, with each thinking that God is on their side and that they are fated by God to spread his True Word and therefore any conduct effected to do that is moral (e.g., Islamic expansion, the various shenanigans the Crusaders got into through their efforts like the sack of Constantinople)
It also doesn't really say how very close strains of the same religion can have very different views of morality (e.g., compare Mormon beliefs on marriage to other Christians; compare catholic views on pre-marital sex to Protestantism) which makes it hard to know which one of the umpteen religions God actually wants to win.
2. God is the cause of and has created a system of morality, but it is up to humanity to do better to strive towards it because we are imperfect. So religion as it exists and as it is practiced may be moral, but it also may be imperfect and immoral because of how we imperfect beings have interpreted it..
This seems to align pretty well with Rabbinic Judaism's overall philosophy and very badly with Islamic theology. Various Christian branches (there are a crap ton of them) are all over the map on this.
I think this is a fine, but unfalsifiable and unverifiable claim. It also doesn't say much about what morality actually IS, only that whatever happens to be moral is what God had intended. We can try to use holy books for guidance, which I actually don't think is a bad idea because holy books are not so different from philosophical treatises at part of their core, but ultimately we need to use our own reasoning and our own assessment or reality and the implications of conduct to assess whether God intended for us to act in a particular way.
A question: Does God think it is morally right to execute gay people or adulturers?
Do we draw on broad moral principles set out in scriptures, or do we look at specific prohibitions as trumping those without recognition that God may have intended morality to evolve as humanity evolved? How do we parse through conflicting or inconsistent moral guidance in scripture?
And if we think the answer in scripture is clear, what do we ACTUALLY think? Do you actually think it is ok to kill people for the "good of the community" or for "sins against god" if they did not really have a choice in their sexual preference (which we now know is largely the case)? Or do we engage in conduct that deep down we think is immoral because we have given up moral agency to various religious leaders and writings?
Looking forward to your one line, dismissive non-response that emptily reasserts that everything comes from God.
