For those interested in studying the Gospel of Mark (we are studying Mark 9 under the insightful Peter Dietsch at our own church this month)... here are some sermons on the Gospel of Mark, from my brother, Scott Redd, who is a professor of Old Testament at Reformed Theological Seminary:
Mark 2: Felt Need, Deepest Need
Mark 4-5: Sea Storm and Man of the Tombs
Those are audio links.