Question about theism and metaethics

Recently I've been thinking about the moral argument for God's existence. I never liked the argument because it never showed how morality leads to God. Certainly, one could say strict materialism would discount moral realism. If you don't believe there is an objective thing called "goodness", than you can't say there is moral goodness. But my concern is how morality leads to theism.

I think asking here would be very helpful. I'd appreciate some explanations, and maybe recommending a book on the topic.

How does believing in objective morality lead to God's existence?

I look forward to having some answers.