This explanation comes is taken from Louis Berkhof's Systematic Theology.
THE MORAL ARGUMENT. Just as the other arguments, this too assumed different forms. Kant took his starting point in the categorical imperative, and from it inferred the existence of someone who, as lawgiver and judge, has the absolute right to command man. In his estimation this argument is far superior to any of the others. It is the one on which he mainly relies in his attempt to prove the existence of God. This may be one of the reasons why it is more generally recognized than any other, though it is not always cast into the same form. Some argue from the disparity often observed between the moral conduct of men and the prosperity which they enjoy in the present life, and feel that this calls for an adjustment in the future which, in turn, requires a righteous arbiter. Modern theology also uses it extensively, especially in the form that man’s recognition of a Highest Good and his quest for a moral ideal demand and necessitate the existence of a God to give reality to that ideal. While this argument does point to the existence of a holy and just being, it does not compel belief in a God, a Creator, or a being of infinite perfections.
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