Part of the Bible that remains obscure to me is that containing the prophets, especially the minor prophets. Isaiah and Daniel are somewhat familiar on account their frequent reference in the Gospel or on account of having a coherent narrative. The minor prophets are difficult on account of their multitude and the apparent sameness of what they talk about and how they talk about it. Nevertheless, the Spirit has willed that these books be written and contained in the canon, so they must be attended to.
Haggai is one of the first to catch my attention. It is brief, only 2 chapters, and yet much happens. The biggest surprise initially is that those hearing the word of God obey and Spirit comes to them. The two main characters were unfamiliar to me, yet play prominent roles in the book of Ezra. Zerubbabel the governor and Jeshua the high priest. Zerubbabel is interesting also on account of appearing in both genealogies of Christ. One cannot understand Scripture without its context.