This step, as Lewis puts it here, is the progression of mankind from awe, to connecting awe with ethics.

Is it possible know if this was reveled, or if it was in our hearts all along?

My gut says that it may have been a bit of both.

But I am willing to be wrong here.

Understand: Humans have a tough time avoiding morality and ethics – as they should.

Judged by its fruits, this step is a step towards increased health. And though logic does not compel us to take it, it is hard to resist—even on Paganism and Pantheism morality is always breaking in, and even Stoicism finds itself willy-nilly bowing the knee to God. Once more, it may be madness—a madness congenital to man and oddly fortunate in its results—or it may be revelation.

-C.S. Lewis, The Problem Of Pain (Amazon)

The second you say “I ought to…” or “I ought not to…” you rise up out of the world of mere materialism and step into a world of morals and ethics.

Sure, you can get “morals” and maybe practical action from the natural world.

But ethics can not be deducted.

(Watch here and here for more.)

This is not an easy issue to brush aside.

All the human beings that history has heard of acknowledge some kind of morality; that is, they feel towards certain proposed actions the experiences expressed by the words ‘I ought’ or ‘I ought not’. These experiences resemble awe in one respect, namely that they cannot be logically deduced from the environment and physical experiences of the man who undergoes them.

-C.S. Lewis, The Problem Of Pain (Amazon)