As described in the "About" sections, Baldwin's stepfather was the source of many of Gabriel's character qualities: abusive, angry, and unkind. In the novel, John's relationship with Gabriel is accordingly tempestuous--and yet, Gabriel is arguably the central character of the book. He is both the heart and the source of tensions in the book; nearly every character and major plot development is defined in a major way by their interactions with Gabriel.
narrow way / broad way (motif)
The narrow way/broad way motif comes from Matthew 7:13-14: "Enter ye in at the strait gate: for wide is the gate, and broad is the way, that leadeth to destruction, and many there be which go in thereat: Because strait is the gate, and narrow is the way, which leadeth unto life, and few there be that find it." It repeats a number of times, and is most relevant perhaps to John, who metaphorically walks that narrow way in his vision (pg. 231).
crossing the river (symbol)
The image of "crossing the river" has passed into American folklore; it can stand as a symbol for death, or for the cleansing that typically occurs in order for a conversion experience to take place--hence the role that "crossing the river" plays in John's vision.
dirty environment as allegory of soul
Several times throughout the novel before his conversion, John describes his surroundings as dirty: his house is, despite the best attempts of him and his mother, dirty. The city streets and the broad way are always dirty (pg. 18, 21-22, 27-28, 36, 54, 219). After his conversion, the avenue (hearkening back, perhaps, to the broad and narrow ways motif) of the church is described as "like any landscape that has endured a storm, lay changed under Heaven, exhausted and clean, and new" (pg. 246). Accordingly, the dirtiness of the world around him becomes a vivid allegory of what goes on in the soul after conversion - "after the storm," to continue the allegory.
Sermons are often used as catalysts for major decisions that Gabriel makes: for example, marrying Deborah and falling for Esther. Both sermons are momentous events in Gabriel's life, as the first (Chapter 2) is part of a revival meeting (where he is being honored by the invitation to speak) and the second is remembered long after Gabriel has moved north (pg. 133).
Go Tell it On the Mountain Questions and Answers
The Question and Answer section for Go Tell it On the Mountain is a great
resource to ask questions, find answers, and discuss the novel.