Study of an ancient text involves the most basic questions, who wrote it, why and when. What were the circumstances what influenced the author's style. Comparative literature studies often illuminate cryptic or esoteric language.
Begin with who wrote it and immediately you will find surprises. Soon after it was written it was attributed to different authors and denied to have been written by the anonymous author of the gospel John. Then pursue the when and whys. Only then are you making any legitimate effort to interpret it.