Robert Frost says: “Poetry begins in trivial metaphors, pretty metaphors, ‘grace’ metaphors, and goes on to the profoundest thinking that we have. Poetry provides the one permissible way of saying one thing and meaning another. ... Unless you are at home in the metaphor, unless you have had your proper poetical education in the metaphor, you are not safe anywhere.” 

Sharing one of his famous poems, ‘The Gift Outright’ - 

The land was ours before we were the land’s.

She was our land more than a hundred years

Before we were her people. She was ours

In Massachusetts, in Virginia,

But we were England’s, still colonials,

Possessing what we still were unpossessed by,

Possessed by what we now no more possessed.

Something we were withholding made us weak

Until we found out that it was ourselves

We were withholding from our land of living,

And forthwith found salvation in surrender.

Such as we were we gave ourselves outright

(The deed of gift was many deeds of war)

To the land vaguely realizing westward,

But still unstoried, artless, unenhanced,

Such as she was, such as she would become.