Mark Horne, the pastor of First Reformed Presbyterian Church in Minco, OK has generously provided his exposition of Mark free. It is available from Google Books, and if you prefer you can also purchase a hard copy here too. The exposition is called “The Victory According to Mark: An Exposition of the Second Gospel”.
I’ve not fully read the book but it is well written and does well at linking Mark’s gospel to the rest of the bible.
Here is the synopsis of the book:
Mark’s Gospel is sometimes assumed to be the least interesting or helpful gospel—it is the shortest and speaks in a plain and direct style. Mark Horne helps us better appreciate this gospel’s goals, by highlighting features not immediately apparent to the modern eye. Horne uses its Old Testament and first-century context to point out the typological roles that Jesus, John, and the disciples fulfill as the new leaders of their nation, a period when the old Israel was both restored and redefined. He shows the gospel’s intricate structures of miracle cycles and other events that bring out the major themes of calling and restoration, all playing into the kingship and triumph of Christ. This devotional-style commentary enables the reader to see through the gospel of Mark’s humble exterior into the riches that lie beneath.