You 'ought' to do this, you 'ought' to do that!.

Concepts of obligation, and duty‑-moral obligation and moral duty, that is to say‑-and of what is morally right and wrong, and of the moral sense of "ought," ought to be jettisoned if this is psychologically possible; because they are survivals, or derivatives from survivals, from an earlier conception of ethics which no longer generally survives, and are only harmful. 

Anscombe believes that historically Christianity allowed for an analogous unifying of the moral life. 


It is correct, she believes, to think of requirements ('what is to be done') as, initially, varied and peculiar to different domains of action--what is to be done by a soldier in battle is different from what is to be done by a merchant exchanging goods in the marketplace, etc. 


But if one holds that the requirements of practical reason in these various domains are expressions of a 'natural law' (divine) which is promulgated, (promote or make widely known an idea or cause).as it were, in the very nature (inbuilt) of the practical reason that we have, then it becomes possible to view what is required under any virtue as falling under the concept of 'required by divine law'. 


source: Modern Moral Philosophy  G. E. M. Anscombe

Originally published in Philosophy 33, No. 124