Okay, okay. Boatloads of poems have God in them, but we don't know of any that describe Him quite like this. There's a definite sense of His being a conglomeration of things, and menacing things at that. The God in this poem is very closely tied to death, and death, it turns out, is a pretty big deal to the living.
Lines 4-6: Our speaker poses three rhetorical questions in a row, which serve not only to make us question the nature of death and heaven, but also to tell us that this isn't going to be a poem where everything will be answered or explained. Nope, we'll have to be satisfied with the mystery.
Lines 11, 22, and 31: This refrain is an odd sort of apostrophe. We say "odd" because a plea like this is usually addressed to a specific person, but here our narrator just kind of throws it out there to… anybody.
Line 23: The description of God begins with a metaphor that equates Him to a furnace (an old, talking furnace, actually). Our speaker doesn't bother to say "God is an old, talking furnace." He just uses a clause that further describes God, like you might say "Mike, that guy down the street." Doing it this way makes it sound like an established fact, rather than one person's assertion. Doesn't everybody think of God as a furnace?
Lines 24-26: That repeated "ee" sound in "teeth" and "feasts" and "gasoline" is assonance, and it has the effect of helping sonically tie together the various pieces that make up this otherwise strange portrait of God.
Line 30: This line uses a couple of kinds of consonance, or repeated consonant sounds. The "l"-sound at the start of "Lord" and "lives" is alliteration, while the same "l"-sound happening inside the word "helpless" is consonant with those "l" sounds in "Lord lives." Despite the strange imagery that our speaker uses to describe God, we can observe an equally strange unity in these descriptions, which is created by all these repeated sounds.