Richard Swinburne's Opposition to the Moral Argument

Richard Swinburne is a genius and we all recognize that. He's in his book, The Existence of God, which I just recently reread. And for the life of me, I'm completely drawing a blank now as to what his argument is. But he finds it the ontological version kind of unpersuasive. It's largely connected with his idea that the necessary truths of morality don't admit of ultimate explanations necessary.