What does scott momaday's poem "Before an Old Painting of the Cross" mean?

Answer 1

You mean Navarre Scott Momaday, and the title of the poem is Before an Old Painting of the Crucifixion.

QUOTED:
I ponder how He died, despairing once.
I've heard the cry subside in vacant skies,
In clearings where no other was. Despair,
Which, in the vibrant wake of utterance,
Resides in desolate calm, preoccupies,
Though it is still. There is no solace there.

That calm inhabits wilderness, the sea,
And where no peace inheres but solitude;
Near death it most impends. It was for Him,
Absurd and public in His agony,
Inscrutably itself, nor misconstrued,
Nor metaphrased in art or pseudonym:

A vague contagion. Old, the mural fades...
Reminded of the fainter sea I scanned,
I recollect: How mute in constancy!
I could not leave the wall of palisades
Till cormorants returned my eyes on land.
The mural but implies eternity:

Not death, but silence after death is change.
Judean hills, the endless afternoon,
The farther groves and arbors seasonless
But fix the mind within the moment's range.
Where evening would obscure our sorrow soon,
There shines too much a sterile loveliness.

No imprecisions of commingled shade,
No shimmering deceptions of the sun,
Herein no semblances remark the cold
Unhindered swell of time, for time is stayed.
The Passion wanes into oblivion,
And time and timelessness confuse, I'm told.

These centuries removed from either fact
Have lain upon the critical expanse
And been of little consequence. The void
Is calendared in stone; the human act,
Outrageous, is in vain. The hours advance
Like flecks of foam borne landward and destroyed.
END QUOTE

So what does this mean? In the beginning he is standing before a picture of the Crucifixion of Jesus Christ, and he begins to wonder what it was like to be Jesus in that moment of death and sorrow. He then reflects upon the details in the painting itself, remarking on how everything seems to be caught in one moment. Time itself seems to stand still or be forgotten. The last paragraph seems to indicate to me that once the moment has passed, the act (of the Crucifixion) was in vain and that it's meaning is forgotten.
I'd never read this poem before you asked about it, so this is only the first impression I get. The link below is where I got the poem, there is a message board there for you to discuss it, perhaps you could try that. Hope this helps!