Psalm for the South

So, upon seeing that this poem strongly revolved around two topics i feel quite adept in (the South and religion) i thought i would throw in my <img src="e.deviantart.net/emoticons/t/t…" width="30" height="15" alt="" title="Here's my $0.02"/> and try to give you some solid feedback for any future literary wonders you bestow us with. In order to provide you with the most detailed and (hopefully) helpful feedback as i can, i'm going to be roughly dissecting the piece by stanza and then, if i haven't already, will answer your specific questions at the end. Just a heads up.

Title: Definitely caught my eye, especially because of the myriad of directions such a piece can go in (titles that provoke curiosity are always the best); also this piece can easily be read as a Psalm and you did a great job incorporating that style into you own very distinct style (a point i'm sure i'll visit later).

First Stanza: Early allusions to the South, psalms specifically, and a metaphor for the bible was a perfect way to start out the piece and set the reader in the right direction.

Second Stanza: Here i'm going to start making some specific dialect suggestions only because i've lived in the South my whole life and honestly don't know many people who know South-Eastern dialects better than myself and there are a couple discrepancies/ways that i'm positive will help improve that are of the piece. (Be aware though, i do know very little about the South-Western dialects as a whole and, when it comes to that region, only really have experience with most Texas dialects so, ya. Grain of salt.)
My suggestions would be to omit the "the" before churches ; and the "v" in "everybody" would actually often go un-enunciated here.
But again, loved the description in this stanza as well as the, possibly imagined, metaphor towards the "Southern nature" of people always greeting you.

Third Stanza: Dialect: i believe "an' feet" would actually be slightly more accurate as well as help the flow of the piece; same suggestion for "an' ticks" as well.
Also, while of is very often pronounced as "a'" (long-a) in southern dialects, the third line of this stanza is one of the exceptions where 99% of the time, people would actually enunciate the full "of".
Your next two uses of "of" are correct though, but i'd suggestion writing it like "I couldn' a' shown you / the long necklace a' stars" just because it would be slightly more accurate to the speech pattern.
And, despite possible subject-tense disagreement, "could" will almost always be "can" in the second to last line.
Again, love the imagery here. Really nostalgic for me especially because i remember running through fields at night and looking for a hill to lie on and star at the stars when i was out of the city; it was the best. Definitely great job conjuring up imagery and thoughts that transcend the written word here.

Fourth Stanza: Dialect: i'd say to drop "'ve" and just leave the start of the second line "i" and add a ' after the "n" in buildings because there is a slight pause/inflection there. Also, i'd suggest using "an' shine".
<img src="e.deviantart.net/emoticons/b/b…" width="10" height="10" alt="" title="Bullet; Black"/>light pollution
<img src="e.deviantart.net/emoticons/b/b…" width="10" height="10" alt="" title="Bullet; Black"/>introduction to the "city life"
<img src="e.deviantart.net/emoticons/b/b…" width="10" height="10" alt="" title="Bullet; Black"/>possible loss of innocence
all these themes are conveyed quite strongly in only a few words here, kudos on the skillful use of brevity in the "turning" point of the piece to transition between the two tones without at all seeming out of place or even, as often is the case with short transitions, abrupt. Well done.

Fifth Stanza: Dialect: Might i suggest "ole' or ol'" rather than old in the second line. Also, more a preference thing than anything else because momma certainly works, but i know that i would be more apt personally to say "ma" here, especially since it is possessive. It really does work either way though so no actual need to change it.
The main themes that i'm getting here is an underlying strong sense of family ties, possibly a moving away from religion (which could be tied to the previous stanza apparent introduction to modern disillusionment) and an obvious Songs of Solomon reference and preference. Perhaps implying that, even should this particular narrator were to move away from religion, it would always be a little part that he would keep (because we always keep something it seems, if only for nostalgic/intrinsic value; or possibly because he understands that some principles should hold true to life even though he doesn't believe in the overarching theme.)

Sixth Stanza: Dialect: i'd suggest omitting that first "the" in this stanza as well as adding a ' at the end of "vibratin". Again, definitely should omit "'ve" and just leave it as "i"
Got to love blue-grass (both the music and the actual thing) Would love to know if the green-ribbon reference is linked with the preluding "grass" and following "thumb-joint" as i've interpreted it (really can't see it being anything different). Definitely shows a really adept and extremely well-constructed metaphor that not only still pulls from the Southern themes, but also gets your message across strongly and furthers the thoughts of potential disillusionment in the narrator. The literary prowess of this stanza is unprecedented, certainly my favorite in the piece. i love, love, love it.

Seventh Stanza: Dialect: i'd say to completely take out "i've" entirely in the second line so long as you don't think it alters the piece too much. i think it would help in a bunch of ways diction/flow wise personally.

Eighth Stanza: Dialect: Ok, hopefully these corrections aren't too drastic but i really think they will help in this stanza particularly.
Line 3: "I don't much like David." or even better "don't care for David much" would really do wonders dialect wise here.
Line 4: graspin'
Line 5: i'd suggest replacing "anything" with "nothing" because, despite the change in definition, they actually are interchangeable down south but nothing would be much much more likely to be used here.
Line 9: an' he
i really can see where the reader is coming from here. i never though David was all of what he was cut out to be either to be honest.

Ninth Stanza - Eleventh Stanza: Dialect: Only suggestions here are to once again to take out the 've and just leave it "i" in the 8th stanza and make it "buildin's" in the eleventh as well as possibly consider making "just", jus' in the preceding line.
We finally see the full manifestation of the narrator moving completely away from religion here. Still holding on to some of the principles and concepts as was foreshadowed earlier such as the desire to dress nicely and use wood and stone, but abandoning a God figure all together as thoroughly evidenced in the 10th stanza. Certainly leaving no room for a misinterpretation of agnosticism.

Eighth Stanza: Dialect: "an' when" in line 2 ; "a' clouds" line 3 ; "an' the way" line 4 ; "an' pulls" last line.
If any stanza in here could possibly compete with your sixth stanza, it's this one here. Perfect job ending on a strong note; further embellishing the conflicts between science, nature, and religion and their constant connection/struggle with each other in human nature.

Obviously i understood the story, the piece connected with me and my past experiences and i could definitely relate to the narrator (which speaks volume to your talent as a writer writing from a perspective that isn't your own, simply brilliant). Not too close to prose, closer to psalms which i think is perfect. The David stanza made perfect sense. Just from your title readers should know to be on the look out for biblical allusions and imagery so i honestly don't think you need to do anything more there. Wonderful, beautiful piece. You are a very adept and brilliant writer.