Full Idea
To call the laws of the supreme Deity good or holy or just, if these be constituted by laws, or the will of a superior, must be an insignificant tautology, amounting to no more than 'God wills what he wills' or 'His will is conformable to his will'.
Gist of Idea
If goodness is constituted by God's will, it is a tautology to say God's will is good
Source
Francis Hutcheson (Treatise 2: Virtue or Moral Good [1725], §VII.V)
Book Reference
'British Moralists 1650-1800 Vol. 1', ed/tr. Raphael,D.D. [Hackett 1991], p.296
A Reaction
This argues not only against God as the source of morality, but also against any rules, such as those of the Categorical Imperative. Why should I follow the Categorical Imperative? What has value must dictate the rules. Is obedience the highest value?