Trethewey's Biblical Symbolism

Natasha Trethewey uses a plethora of Biblical and religious symbolism in her poetry collection Native Guard in the first section. The introductory poem which leads the entire section includes the river Jordan: "I'm only going over Jordan / I'm only going over home." The first poem in the first section is titled "Southern Crescent," and Southern Crescent refers to the old train system that ran through the South and the actual waning of the moon is considered the eye of God, for it resembles an eye and eyebrow when the North Star rests directly under the moon.
Trethewey also uses fruit, very symbolic of the fallen Eden, and may even represent herself in a wayward momentary loss of the memory of her mother in "After Your Death." More religion pours out with the mention of Ash Wednesday in "Letter," which is led by "What the Body Can Say" which suggests hand gestures in the form of prayer and/ or communion: "just as / we open our mouths in church to take the wafer."
Her first section is becoming more and more Catholic in nature, even more obvious in her addressing of the mortal sin Vanity in the poem "Genus Narcissus": "a whisper, treacherous, / from the sill. Be taken with yourself."
Also, she even leads us into the second section with the first poem titled "Pilgrimage" which offers more Catholic and possibly other religions to the basket. Mostly during the Medieval Ages did the pilgrimage become popular, way before the Canterbury Tales, and right around the time of the Crusades, which was not just a search for God, but remission of sins and absolution of guilt and the offering of penance.
Is Natasha Trethewey searching for penance? Is she harboring some sort of guilt?